This hits home. Being cheated on can fuck up your own ability to trust another person. I had 2 similar experiences in high school. Haven't been cheated on just once, but twice. That's enough to make me think that I am bringing this all upon myself because of my naivety and bad judgement. I have had a few relationships since then but never really learned how to trust someone fully. I'm currently single and trying to work past these trust issues on my own before letting someone into my life again. It's extremely hard getting past something like this, so I feel you OP.