Is he too old ? What would u do ?

21/F “40/M

I’ve been seeing a guy I met at work,we were really close friends then we ended up sleeping together at his one night (which I really regret and should have never done). I think I’ve realised the age gap and that his too old for me and we at very different times in our life . I miss being just friends with him but I know he really wants a relationship.He generally is lovely but not just not into it