So by the title y'all probably think I'm this terrible person for trying to ruin their relationship. but let me explain.

Backstory: I (17F) and my best friend Jen (17F) have been friends since middle school even though we went to elementary together. Back then google chat was like our social media. Since no one was quite at the age for Insta or Snapchat etc. we would use our school emails on google chat. People would create groupchats and people would add their friends, and those friends would add their friends, and so on until people from completely different schools were in it. This is where she met a boy named Nik. He went to a different middle school than us and was a year younger than us. They started getting close and eventually started a relationship. I told her not to do it but she didn't listen to me. That's when shit started to happen. He became a little manipulative, telling her that if they hadn't started dating he would've killed himself or that if they ever broke up he would kill himself. I kept on telling her to end things but she was so paranoid of being the reason her would... ya know.
Skip to my Freshman year in Highschool. Me and Jen go to different Highschools but are still in the same district. Nick was in 8th grade at that time. They were still dating and had actually met up a few times and let me just say... not only is he younger than her and super immature/manipulative, but he is also ugly. How I like to describe him is 40 year old looking hobo drug dealer aesthetic. He legit looks like a pedo. He had also admitted to Jen that he watches porn. I was still telling her to end it with him but he was still telling her that he will off himself if she ever did. I seriously don't approve of this man and I never did.

Skip to my Sophomore year in Highschool. AKA last year. Nick was just starting Highschool and was going to a different school than Jen and me but again, still in the same district. He had stopped telling her he will off himself but instead would tell his friends about it. I know this because his friends told Jen, behind Nick's back, what Nick was saying. At this point she started to not like Nick as much. She started to notice that he wasn't as great as she thought he was, in my opinion he was never great. Jen told me she started to like this one guy at her school and wants to end it with Nick but doesn't know how since she still doesn't want to be the reason he offs himself. I told her to just get it over with and that she'll feel a lot better.

Jen is a beautiful girl and is so nice and sweet and deserves so much better than Nick. I try to tell her that he isn't the right guy for her and that she could be with a man that can treat her right. I also think that Nick is too immature to date and probably isn't ready for a relationship, especially with a girl older than him.

Anyways summer after Sophomore year me and her called everyday for hours. Catching up on the drama and school and shit like that. This is when things went Nick went suuuuper downhill. He was becoming obsessed with her. Like twilight obsessed and it was honestly really creepy. He would tell her that he can't live without her and was trying to convince Jen to tell her parents about their relationship. (I forgot to say this earlier but Jen isn't allowed to date.)
Anyways he also would try to meet up with her a lot and whenever they did, she would tell me that literally all he wanted to do was makeout. She said a few times he tried to push it further but that she refused. Eventually Nick's parents found out about his relationship with Jen and told him that he is too obsessed with her and needs a break from her. They took his phone for a week although that didn't change anything besides the fact that he was more secretive towards his parents. Jen told me she didn't know what to do because then Nick started saying that if Jen didn't tell her parents, that he would. Oh! Also, when Jen wouldn't tell Nick her address he started texting some of her friends begging them to tell him.

Okay so here's where my title starts to make more sense. It was still the summer after Sophomore year, middle of summer actually and me and her were on a phone call. We had already been talking for a few hours and then she opens up to me and tells me how she's scared that because she doesn't want to do sex with him that he might try and do it with someone else. And considering that he watches a lot of porn, still, it's not completely far fetched. I hold her that if she is paranoid about it to talk to him about it and break things off with him. She told me that she is too nervous to break up with him so I told her, as a joke, to just act super mean or disgusting or something to make him break up with you. That's when she had an idea to prank him. She told me to text him as some random girl obsessed with him and see what he does. She gave me his number and told me that we can use this as a excuse for her to break up with him, if he does anything. We did a FaceTime call and I shared my screen with her and I started texting him. I pretended to be this girl named April who was obsessed with him. He asked for a pic of her so I found a random picture of a pretty girl on Pinterest. Nick told "April" that she was really absolutely stunning and totally his type but that he was already in a relationship. That's when Jen told me to try and convince him to break up with her for April. I even went as far as telling him I wrote a song just for him. Jen then told me that he was sending her screenshots of his and April's messages. Jen showed me the screenshots but what was funny was that he sent Jen everything except for the parts where he told April she was pretty, nice, or his type, etc. He then sent Jen my/April's number and told Jen to text April. Jen changed my contact name in her phone and pretended to text me and would send screenshots of our convo to Nick. Then Jen told Nick that he should get with April and not be with her anymore. She pretended to be sad but we were full on giggling while still on the FaceTime call. Eventually I went over to her house that same day and we continued the prank. Jen told Nick that she was "mad" at him for telling April she was his type or that she was pretty. He apologized and told her he was in love with her. The prank or whatever it was backfired and we were both disappointed. She was upset the plan didn't work and that now he's even more obsessed with her. So me, as April, told him that I was thinking of a different Nick and that escalated to "I will steal your girlfriend from you." At this point is was all just for shits and giggles and we were doing it just to get a good laugh.
(I will say that for most of the time Jen was telling me what to say to Nick.)

Anyways skip to present time, I am a Junior and so is Jen and Nick is now a Sophomore. He still has no idea it was Jen and me and he actually will still text "April" and whenever he does I call Jen and we continue the "prank". I still tell her to end things with him especially since now he proposed to her. Gave her a ring and everything. He has planned their entire future together. A month ago Jen passed the ACT test and got a really good score on it and wanted to get into college and all this stuff. She had a plan for her future, but then Nick proposed to her and told her that he was gonna go to college and also become a famous musician. So now she told me that she is no longer gonna go to college and told me Nick's plan for them.

After Highschool she is gonna work and save money then when Nick graduates they will move in together and he will go to college while also working on his music while she takes care of the house and works and get married and have kids and all this stuff.
His friends and parents all think this is crazy and that he is super obsessed with her.

I told her that she is really smart and that she is throwing away her knowledge and potential for this man. She could get into an amazing college and do so much with her life but she shouldn't throw all that away for a boy. A literal boy. He is so immature and planned his whole life with her but by doing that, he also planned her whole life as well. Which is nothing like what she wants. I can tell she is very unhappy and I don't know what to do. I really want to help her but I don't know how. Please help me Reddit. AITAH???