How can i get over this?

Ever since my first heart break 3 years ago I've been really scared to feel those emotions all over again to the point I never got another boyfriend until now. I know I'm very much in love with him and he loves me too but my fear of being hurt haunts me so much because you can never be too sure you know. You've been together for a little over 7 months now and i wish we could last forever like in one of those story books but I know that's not being realistic. How can i get over my fear and finally be free to feel like it's ok to love without thinking of the negative?