Can I get some advice here please

So my bf and I have been on and off since high school. Specifically, 3 years on and 2 off. My mom has told me numerous times why I haven’t dated anyone else. I’m only 21 and obviously I’ve been with the same guy because I still have feelings for him.

It makes me feel so sad and unsupported that my own mom wants me to literally go out with other people instead. Am I doing something wrong? Should I be dating more people? Am I wasting time?