Trust Issues..

So, my boyfriend and I started dating in August of 2012. In November 2013, I found out that he had cheated on me (nothing in person, but was on a dating website messaging girls). He said he only did it because he thought I was going to break up with him since we were fighting more often because of stress. I decided to forgive him, but I've had horrible trust issues and jealousy ever since. This past July we broke up for a month because of issues we both had. He realized that I was not the problem, and I knew I didn't want to be without him so we got back together. But during the time we were broken up, he hung out with & kissed another girl as he was trying to fill the space in his life. Granted, I tried to talk to another guy during that time too, so I couldn't say anything. But with that and what has happened in the past, I have trust issues like no other. I love him to pieces, and he is my soulmate, but he is flawed and I am scarred. Do you think I will ever get over feeling like he is doing something behind my back? Have you ever been in this situation? Id appreciate any advice!