How do I learn to love again?

I've been in love with the same jerk since highschool, now on my final year of college and still hung up on him. I feel like I'm incapable of even thinking about loving another man, because I've only ever loved him! We've been fwb, never really dated, he's slept with other girls while keeping me on the side and all I could do was accept it, so I don't want to be with him, but he's always there for me when I need him and i know he'll never abandon me. How do I move on? I want to be in a healthy relationship and get over him. Any advice helps!!