Learn to trust again, and trust wisely

I’ve been hurt a lot of times already because I used to trust people too much. My best friend in high school wasn’t a good person to me but I was too nice to ever let her down in return. I didn’t want to “stoop to that level” and while that is true, I think that’s also called standing up for yourself. Then my boyfriend. Then another best friend. Then my boyfriend. Not kidding. The sad thing for me is that now I relized that there is one person I do trust now and it scared me so much that I accused him of being dishonest since I’ve been wrong so many times about people before. I have a problem…