What should I do, i broke up with the love of my life so I thought. we were together for about 10 years.?

everything was OK until she met some guy at uni, then she start spending a lot more time at uni, most weekdays she would come home at 11 or 12am. she would insist he was a friend I chose to believe her, but i think at the back of my mind i was doubting her. something happened and she near got kicked out of uni because of this guy. anyways I asked her to stop seeing him she was like he is my friend, it wasn't until one of her friends told i wouldn't speak to him again, that she stop talking to him. couple of years later we had a child, when the child was about a yr saw that she was talking to the same guy and the message were explicit. anyways, things just kept going back, even tho i loved her this was making me less affectionate towards, after a while we broke up, and this guy was the first person she call, and i found out that they went cinema and dinner a week or so after we broke-up. anyways 7 months after we broke up, we were still friends we would speak to each other comfortably, then she started getting more text the usual, i started to get curious so one day i check her phone when i went to see my son, i saw a man's penis and a lot of messages between her and this guy, i asked her about it she said she was seeing him and was planing to tell once they got serious, i also saw that she was talking to the guy she met at uni, telling him about my son, i question she reply with he is a friend, i told I don't comfortable her tell this guy about my son. anyways i left her house, shocked and angry. she texted me blaming for ruin her life and not doing enough, i was like ok. she was like can we still be friends because of how long we were together and we had a child, i was like no, so she cut me off she doesn't talk to me anymore, when i call to speak to my child she doent pick up she doesnt reply to my messages. can some give me some advice. i feel like the kind of friends she has haven't helped to, cause all they think about is men.