Boyfriend talks to ex even though it breaks my heart. Need some help!?

I've talked to my boyfriend three times about not talking to his ex. Every time we talk, I let him get his way because I can't stand it when people are mad at me. Recently, I've become really hurt by his actions. He let his ex come over to his house when his friends were over and ';forgot'; to tell me. He also ';forgot'; to tell me he had lunch with her last week. I know he talks to her weekly, if not daily, and that really rubs me the wrong way. Whenever I bring this up, he says I don't trust him and that I have a trust issue. Maybe I do, but it's hard for me to trust him when she's over and he doesn't tell me. I've talked to most of my friends about this, and they say he should stop talking to her. Am I over-reacting? I honestly feel like he has some sort of feelings for her because why else would he not tell me he saw her? I ask him why he wants to be friends with her and he can't answer me. I wish he'd come clean. If he has feelings for her, that's fine, I'll leave him. Also, he hasn't been acting like a boyfriend lately. He hasn't done anything romantic in forever. I told him that last night and he said he didn't realize how bad of a boyfriend he is. He also talks to his other ex's too. It seems like he cares more about his ex's than me, and that really hurts. My previous boyfriend cheated on me with his ex, so it's in the back of my mind that he could cheat too. I need some help. What should I do?Boyfriend talks to ex even though it breaks my heart. Need some help!?
Talking to her is not the problem, lying about it is. It means he is trying to hide it which means he is doing something wrong. He obviously still has feelings for her and does not care what you think or he would stop being so ';friendly'; with her. Tell him he stops or you are done.Honestly, I am not a jealous person but, I would not put up with that.