I'll have a TLDR version first and give more detailed background below for people who want it.

I (32m) have an 8 year old son, Cole, with my ex (32f). We share custody of Cole 50-50. My ex has been remarried for almost 4 years and her husband is Tyler (35m). There's a lot of bad blood because Tyler is the other man and a lot happened. So things aren't warm between us to put it mildly. My ex and Tyler did not support Cole joining cooking and baking classes when he expressed an interest in joining them. They didn't feel it was a boy activity. My ex eventually gave in because Cole had no interest in football and basketball like Tyler really wanted. Tyler has come around very recently and he has expressed hurt that Cole never invites him to family participation days at his classes. He invites me and his maternal grandma mostly. His mom gets some invites. My ex and Tyler don't feel I'm doing good by Cole because I won't encourage him to invite his stepdad.

And maybe I'm not being fair which is why I'm posting here. AITA?

For those who want more background on everything I'll provide it here.

Like I mentioned above. I share custody of Cole with my ex. When Cole was 3 we found out she was pregnant again. That very same day I found out she had been cheating on me with Tyler for more than a year at that point. I ended our marriage and told her I wanted to find out for sure if the baby was mine or not. She told me we'd have to wait and she wasn't risking her child for anyone.

Tyler knew about me the whole time the affair was happening and for reasons I don't understand he expected me to happily let him raise the second baby regardless of who the actual father was. I told him I wasn't going to be pushed out of the baby's life if they were mine and I already had Cole so I wasn't going anywhere. He told me at the time Cole didn't need me. I told him he did need me and so would the baby if they were mine. I told him the baby would be defaulted to mine at birth anyway because I was married to my ex. This angered Tyler and he insisted on doing the DNA test while my ex was pregnant. My ex gave in and the test proved Tyler was the father of the baby.

My ex lost her daughter with Tyler at 19 weeks. She blamed me. Even though Tyler insisted on the test she blamed me. A few days after the loss she suffered a post-birth complication and needed a hysterectomy. Which was also blamed on me. Once they lost their child there was never going to be any good between us. But the hysterectomy pushed us into a very bad place where they wanted me to leave and let them raise Cole between them while I wasn't walking away from my son and hated the two of them for the affair.

I admit it made me sick that Cole might grow up to see Tyler as his second dad. That he might even love Tyler eventually. It worried me too. But I went to therapy to try and do right by Cole.

My ex's mom sided with me in the breakup and had a massive fallout with my ex. Ex's mom told my ex she was a disgusting cheat just like her father. So ex has always held it against me that I remained on good terms with her mom and that her mom sees Cole through me. She wanted her erased from their lives entirely after she compared her to her father, who cheated on her mom.

There were times we ended up in court over stupid stuff. After my ex and Tyler married they wanted to change Cole's last name to theirs, which was rejected. They wanted primary custody on the argument of a two parent household and they were denied that. They wanted Tyler to have equal rights to Cole which was also denied. Ex wanted to change the school Cole was in after he started and used the court to try and do that and was denied.

When Cole expressed an interest in the junior cooking and baking classes I was very much in favor but my ex and Tyler resisted like I mentioned. They used a lot of stereotypical arguments about it not being for boys. Tyler said he wanted to play ball with Cole and no son of his would be like that. I told Tyler Cole was my son, not his, and he was proving not to be a very good stepfather. My ex raged at me for saying Tyler was a stepfather when I cost them the chance at being parents together. She also wouldn't give into the idea of the cooking and baking classes. It took months for her to accept them and give permission and it was only because she was losing her relationship with Cole.

Tyler didn't come around until recently and he tried to get involved but Cole doesn't have a good relationship with Tyler and this is just one of many times according to my ex that Cole makes it seem like Tyler isn't even family let alone a parent. I can't say that saddens me. But I was told since they can't have more kids together then I should do a better job of sharing the role of dad with Tyler and letting Cole thrive with the benefit of two dads.

We communicate through two different parenting apps. And this has all been discussed there although I don't really reply to this kind of thing much. I don't feel charitable toward my ex or Tyler. But I know that might be selfish because maybe it's not putting Cole first. I don't think Tyler is a good stepdad to encourage that relationship between them but maybe I'm extremely biased.