This is messed up but my advice is to do what I do in these situations. Same thing happened to me and my friends, this guy would cling on to us when we were smoking weed and invite himself to whatever we did or went. One day after a smoking session my friends and I were gonna have a night out, and all of a sudden this guy shows. So we drove as far away as we could in the timing of 15 minutes and we pretended to go to this tack bell ( according to him we were just gonna go grab munchies. So this guy has a habit of going to the bathroom before he even orders so when he did we wasted no time and ditches him there. He never showed up to any of our smoke outs again. I already know you were straight up with her once, so since that didn't work out sometimes you have to take extreme measures.