Bleank

I'm 25. I've only ever had the one gf. It's been going on for about 4yrs now. Recently I found out she'd lied to me about a lot of pretty important stuff in that time. She kissed a guy, went out on a date with another. I'm not an idiot who's superclingy but I'm not a hothead either. She told me about these things, I say that's a plus and she never slept with anyone, I'm fairly sure. She says she was just being stupid etc and it's all over. Despite it all, my feelings remain the ssme. The problem is that trusting her is an issue. I want to but my brain just won't stand by and watch so I get suspicious and the memory just floods back which just serves to fuel my doubts. I'm fine now, I guess, but am I just kidding myself. Can I make it work or is my mind just slowly unravelling and given time will reach a breaking point, assuming all she said about loving me is true