<human>: I'm not even sure where to start with my relationship. T (27m) and I (24f) have been together 5 years and have a 3 year old son together. We currently live together, but it has been a struggle getting to the point that we are now. T has cheated on me, while I was pregnant. I thought we had worked through that, but it definitely had an effect on me. I now hate any girls he talks to, I had to delete fb just to not get unreasonably jealous. We recently have been arguing about instagram and how uncomfortable I am with him following all half naked chicks. 

I looked on instagram this morning and the woman (30f) he cheated on me with is now following him. He isn't following her, but I want her gone. She always seems to pop up and she's always hanging over this relationship p. Now I can't help, but wonder if they're fb friends or texting. 

I love my bf, I love my family, I thought we were passed all this. I don't know how to approach him about this shit again because it's always me snooping and "trying to catch him doing something" and I just need to trust him. I know our relationship won't last if I don't learn to trust him again.

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<bot>: my bf cheated in the past and now the girl he cheated on me with is following him on instagram. How do I approach this and learn to trust him again?