somebody please help me

I don't want to feel this way anymore, I broke up with a boy I was completely in love with, I gave him everything, my virginity, all I had, I tried so hard to be enough for him but the whole time there was someone else, we broke up 3 months ago and I can't seem to move on, he still comes back to me and uses me to do stuff with but I'm too weak to say no, I feel so worthless and I'm so broken and I don't know where to go from here. I just need advice because I can't keep feeling like this