Need advice on how to heal or end a relationship affected by mental illness

(Long post, need relationship advice having to do with mental health) I essentially abused my (ex?) boyfriend for our entire relationship. (Verbally and manipulative). None of it was malicious, I do genuinely love him very dearly, as he is my best friend. I realized a change needed to be made and have worked tirelessly to fix it and heal our relationship. However recently, his dad (known to be quite manipulative and controlling) got onto my bf for being “self absorbed” over cooking a steak and making the house Smokey. As I left the room to save my bf the embarrassment, his dad came after me as well, calling me self absorbed too. Obviously, I was quite offended and took it as an attack on my character. He managed to convince my bf that I am this as well. None of my close friends and family agree, and they are all the type to call me out anyway if it were the case. It’s simply not true. On top of this, my bf can’t give me a consistent reason for why he’s not proposing to me after 3.5 years in the relationship (we are adults). At one time it was because I was manipulative, now it’s because he’s not ready. He’s made 0 preparations to become ready in the past 3.5 years. All of this combined resulted in my breaking up with him. Of course, I had morning after regret and called him drunk this morning begging for him back. Now we’re not broken up but “on a break” (insert Ross gif here) until Saturday after we’ve thought about the situation. I feel so conflicted. Did my mental illness and lack of self control doom the relationship? I know people with bipolar typically have difficulties maintaining stable relationships. As much as I feel he’s hurt me through all this, I have to think that it was possible that I caused it in the first place by being so mean early on. It’s possible I caused so much damage that he doesn’t even realize it and is now hesitant to marry me. If so, does anyone have any advice on how to either heal the relationship or end it and avoid causing similar problems in the future? Or is his dad just a cruel man intentionally causing issues between us? He does have a history of proving he doesn’t like me from the start. He didn’t agree with my bf dating so young (is 18 even young lol) and wouldn’t allow him to visit me in college. It’s just hard to tell what problems I’ve caused and what I haven’t because of my illness. Any advice would be well appreciated!