I think about the first girl I dated way too much. Advice?

I’m sitting here a few relationships later and I still want to check on her and see how she’s doing as a person. I don’t know if I what I’m feeling is a I still like her vibe or if I just kind of wish we still communicated as friends. We kind of said we would but that’s not really the way things went. I do see her on social media from time to time. She was really the first one to reciprocate my feelings so I guess I’ll always remember her in that way. What should I do about how I’m feeling?

But either way I’m still very content to just leave what we have in the past.