I will try and make this as brief as possible as this is a little lengthy.
I have been with this girl for 16 months. She is only 24 and previously married with 2 children which she shares custody with the dad. We started seeing each other soon after they split and they were still living together.
She got her own place September last year and has her children mon-thurs whilst he has them thurs-sun.
In November I turned up at the flat one night and found her on the sofa with an ex bf. I got angry and stormed out, it turned out she slept with him. Filled with regret she asked me to come over the next day where she begged me back. Despite everything, I did.
It's been a hard road since then but we have got on really well. I know this might be hard to believe but she was really in love with me. She would tell me every day, text me frequently telling me how much she loved me etc so despite what had happened I was confident of how she felt for me.
Until 2 weeks ago.
We had a stupid row over something trivial to do with the fact I was unhappy about her having her sister stay over rather than me when my dad had been in hospital and so we only had the one night together that week. In the end her sister didn't stay, I did, but she wasn't well so I looked after her and cooked her dinner.
The following day she broke up with me. It later turned out a couple of days later that over the past 2 days she had been talking to some guy on the internet. She took her keys back from me 2 days later on the weds but we ended up sleeping together. The next day she decided she wanted to try make things work and we had a really good night together so I stayed and got my keys back. The next night (bare with me!) she ended it again but I stayed and we slept together with her in tears. She went to work the next morning and left me there, she then rang and text me constantly in the morning saying she didn't want us to end. When I replied later that day, her attitude had changed. I knew something wasn't right.
Cut a long story short, the guy she met on the internet days earlier, she had gone out with that night. She then took him back to her flat where I caught her again. This was 2 weeks ago.
Since then I've seen her twice last time we slept together again. I've become so angry and told her after what she did to me I wanted the money back I leant her when in debt and I told her I should tell her family (who liked me) exactly what she did. She is now in panic and won't leave me alone.
I was supposed to meet up with her to discuss things but she is at her parents and won't let me at her flat for some unknown reason. So I've refused to discuss anything unless it's in a place where we have privacy.
I know I should be rid of her and be happy she is gone. But I'm so angry and hurt by everything she did to me I feel I should do something as revenge. Such as take her to court for my money, or write a letter to her parents to explain what happened as she always portrays herself to be totally innocent.
What do I do?