I 16f am the middle child in a family of 4. Katie 41f, Jack 19m and Lilly 13f all fake names, dad 47m can be classed as a deadbeat but I still see him used to be once a month for 12 years but now can be regular and he does pay child support. Katie and dad aren't married he cheated and they divorced, I would say they have a good co-parenting agreement but I only saw him once a month so idk. So for the last couple of years Katie has been bad mouthing dad a lot and I sometimes do it because Jack is his favourite for more then 4 years. And over the years I've been feeling depressed about many different things I don't wish to disclose for personal reasons. A little bit of backstory to why I am here, dad moved closer to us after 12 years of living more than 3 hours away with his gf and her kids and a couple of weeks ago dad purposed to his then gf after moving and Katie went nuts she kept bad mouthing him and their new home and how he one upped us by getting a home with one more bedroom and she just kept going on and on. Now they have a puppy and she hast it because now they have a dog like we do. Katie doesn't want me or Jack to visit, keeps trying to bribe us not to. And it was just getting to much till she eventually stopped but that was after Jack and Katie had a huge fight about it.

To the main problem for as long as I can remember Jack has treated me like poop because he's older and my brother but its getting to me now and idk what to do as Katie only stops it when I start talking poop to him and call him names he calls me but I can't say the names here due to had bad they are. Jack just treats me like poop and Lilly has been doing the same and they do it together sometimes, they think they are funny and its all a joke but it isn't and it really hurts me. And non of them seem to get why it hurts when i get called all sorts of names under the sun. They expect me to be all fine about it and laugh with them and they call me an idiot and dramatic when i tell them how i feel. My self esteem and confidence has been at a all time low since high school and hasn't recovered much since i left due to how bad i have been picked on at home since it's everyday. It also doesn't help how Katie's mum (Abbie fake name) is and how she treats us on top of everything else. She shames us, ridicules everything we do. Katie tells us not to start anything or rise up to her, I haven't for a while now but Jack and Lilly don't get it Abbie is like it because she had a mental break before i was born and wasn't the same after. This is all needed for what happened that broke the 100ths camels back. A couple of nights ago we were having dinner and Jack had already made fun of me before it. Katie asked him to pour him and her a glass of drink now at the time I didn't know that the drink was only bought for him as no one told me beforehand. So he poured himself one but not Katie so I had to do it but when i did there wasn't enough for a full glass for me, i wouldn't say i was pissed but wasn't happy as i also like the drink. Jack looked at me and said "you didn't pour that well did you" that had pissed me off because it wasn't my fault he had filled his glass to the brim while i poured Katie a sort of full glass while it only left me not even haft so i said " well if you hadn't pored a big glass i would have more" this just set him off he started shouting at me swearing took my glass and gave me his and he was pissed. It didn't help that Abbie walked into the room and said "poor girl" because even though she can be rude to me she knows how I am normally treated at home ignored, picked on and then blamed for everything. So because Abbie said that Jack.Went.Mental he started having a go at her and she went off at him, I didn't so anything but sit there cuz what am i meant to do. Katie is trying to stop both of them but was failing. Abbie stopped and went to go eat in the kitchen and Jack took his dinner and went to his room. We all ate in silence till Abbie's husband Brad fake name came and joined us for dinner. No one said anything to him cuz we all knew it would be a mistake to. After dinner they went home and me and Katie didn't talk, but the next morning she was shouting at me and Jack, at Jack for having a ago at Abbie and at more for stirring it up and saying i got my wooden spoon and made it all my fault. I didn't think it was so i decided to not talk to anyone for a couple of days to cool off but i got mocked and picked on even more by all of them, i was sworn at, name called and everything just for trying to cool down. I decided i had enough and started talking to everyone properly yesterday evening. It was going ok till tonight when Katie decided to drink to much and she's now a light weight so she wasn't acting normal. We were having dinner and all having a good conversation till Jack left, that's when it went down hill. Idk how but the conversation turned to how Katie wanted to check out a few weeks ago and told me about it, idk what to say to that how am i supposed to react to your other telling you she wanted to send us away and end her life. I couldn't handle it and broke down to crying cuz i didn't know what to do. If i couldn't handle it how is Lilly a 13 year old girl gonna handle it so i told Katie to not tell Lilly and to never say that around her. Katie got defensive and moody because i didn't want her to say it so then Lilly got mad because i told Katie not to tell her so then they were both shouting at me so i just sat there till Katie got onto a completely different subject and had a huge rant at me of how Thursday dinner was my fault and how my room being messy is coursing her stress and how i am the problem. She just went on and on and i just sat there taking it all in. We had had this conversation before, she also uses this time to talk about her problems so she stopes trashing me to talk about her life and what's wrong with her like i am her therapist but i get that she also has no one to talk to as she is a single parent living off one income in a house of four. I get she is struggling but i am as well, of course different issues but she doesn't seem to get how its effecting me knowing how we are struggling so much and worrying about money all the time. I get she has problems and needs to vent but i don't think I'm the right person for it.

I don't know what to do anymore as i can't handle all the stress and dark thoughts in my mind, i just cant take much more of this it's like my feelings aren't taken into consideration at all by anyone. I can't talk to anyone about this because how do you explain all this to someone. I did have a councilor but that was because of a separate issue and couldn't take about all that's going on but i only had one session then they left and i haven't spoken to anyone since. Oh also to add my relationship with my dad is rocky as Jack is his favourite and i am mostly ignored out of me and Jack since they always have something to talk about while me and dad don't. He also makes comments towards me but about a different issue. I have left stuff out that is about me personally and don't wish to share.

This is just for me to vent but any advice will be great as well. So am I the AITAH for how i feel about my family.