Insecurity and cheating in relationships

In all my past relationships over the past few years I have been unable to remain faithful as I have anxiety and insecurity that causes me to resort to cheating as a solution. I was hurt badly in one of my first relationships and since then have never been able to trust another guy.

I cannot stay loyal, even when I am in love. That is the case now. Yet I have convinced myself that my current boyfriend will suddenly leave me, my worst fear, which makes me feel the urge to cheat so I am not left alone if something bad were to happen.

I can’t help it. I get so worried with my boyfriend even though everything is going well and we are happy with one another, I can’t stop thinking he is hiding things from me. I love him but I still find myself organising to see my side guys.. not out of interest or love for them, but because I am so afraid of being heartbroken in my own relationship. I really need some advice.