Ex in prison, I'm in trouble....

please be patient as this is a long story. I'll start by explaining my ex a little bit. we were high school sweet hearts, and we were together for 3 years. he grew up in a very broken household. and had anger issues. He never got violent with me, but explained that he was terrified of becoming his dad. We had many discussions about this topic. Anyways we broke up when I found out he cheated on me. But I never stopped loving him. fast forward a couple years, I had heard numerous stories of him beating all of his girlfriends, but I was still in love and still wanted to try and talk to him. well we met up, definitely hooked up, and talked quite a bit about what was causing him to repeatedly hurt these women and why he never did with me. he explained that he knew he had issues and was trying to get on new medication to control his anger. He said the reason he never put his hands on me was because, he loved me so much, and I knew how to calm him. after about a week of talking he said he had to be honest with me, that he had a girlfriend. I was upset but grateful that he was honest about it. I was going to stop talking to him after that.... but... I went to a mutual friends house that week. where he showed up with his new girlfriend. I was obviously upset and walked out.... when all of a sudden his new girlfriend comes to check on me. Mind you, I never met her before in my life. she came outside and sat on the curb with me, when I was honest with her. She instantly became one of my best friends. And afterwards all three of us would hang out daily.... definitely not a good idea but I really liked her, and I still wanted to be around him. until one day, they got in a huge fight in front of me. He punched her once, really hard (bad black eye). I tried to comfort her.... and she said "don't call the cops, and go calm him down" right away he regretted what he did.... he cried, he appologized, he was so mad at himself. whatever. Butttt. I took her home with me. I took her to the hospital. I comforted her. She broke up with him, and I took her side... That girl and I, are still best friends. He however was mad that "I chose her over him". and it's been 7 years since that happend. In the past 7 years, I have moved, gotten a decent job, got married and had a daughter. I haven't talked to my ex since. Well here is my issue. I've never stopped loving him, my marriage is shit, I just had a miscarriage a week ago, which my husband has been very unsupportive of. I'm just going through some rough stuff right now. well about a month ago I saw a Facebook post about how my ex is in state prison for a LONG time for doing the same thing. I felt so bad for him, because he truly is capable of being a great guy, he tried to seek help when he was younger and no one would help, he used to cry to me about wanting to be better than his upbringing. And I have seen the best side of him. well I couldn't sleep and it was really bothering me, so to make myself feel better, I sent $20 to him. I was told it would be anonymous ( I checked because I didn't want him to know it was from me)... well his mom contacted me, and said he really appreciated the fact that I did that, and how he never would've expected me to help him, how out of everyone in the world, I know him the best. blah blah blah. And he wanted me to write him..... well I'm married and if I did write him, I would get a letter back in the mail, and if my husband saw I was writing to my ex in prison he would lose his shit. So I never wrote, now I get another message this week, "he is going through a really hard time, just wants someone to talk to, and just wants to say hi, he was wondering why you didn't write him yet." I explained that my husband would flip otherwise I would. I do actually want him to know, that I don't think he is a monster, that I knew he needed help, and that he is capable of being better. (he was diagnosed with intermediate explosive disorder). Anyways she said she is going to give him my phone number. which I am super nervous about. he is supposed to call this week, I know I'm doing something I shouldnt, and I know all you ladies are probably thinking "what the fuck, NO" but I will never stop loving him, and never stop wondering if we never broke up, would it have been bad or good. would he have hurt me, or would he be a better person. where would I be right now. because I regret my marriage so much, and I don't know how to leave. ugh ladies, I'm in trouble .