Need some help!

I'm 28 years old with a 2 year old son. I have been with my SO for over 6 years. He has cheated on me numerous times or dumped me because he found someone "better". He also wanted to go on a break because his ex was coming into town. Yes I stayed through it all. I have severe anxiety so being alone scares the hell out of me not to mention he was and still is my only boyfriend. So the connection there is strong in a way. Well I cannot forgive him for cheating cause it's ALWAYS on my mind. How can it not be? Whenever he goes out or whenever he's texting, I think he's cheating. Well lately he's been "talking" to this girl he cheated on me with and I lost it. I have been depressed ever since. I'm to the point I no longer care if I am alone, I just cannot live with not knowing if he's cheating or not. What would you do? I love this man so much but it's always in the back of my mind that he is cheating. He won't do counseling so that's not an option.