I still have feelings for my ex.

The title says it all. I have feels for him and I haven't necessarily moved on from him. Jack and I have a weird friendship not like most others will say they have with their ex. We are still best friends like we have been. It's just, what broke us apart was distance since he lives in the UK and I live in the US. Another issue was that before we became together, he always had the thought of possibly being gay. One day he'd like me and the next he'd be attracted to men, and woman would be a complete turn off. It's always a back and forth thing. Just a month ago he said he still wanted me to come to the UK and have a child with me. Just what? I just don't know what to do. I really don't want to cut all ties with him either since our friendship has lasted five years. If you have any thoughts/advice please share.