Ex boyfriend misses me ??

My ex broke up with me and wanted to end on good terms, however we haven’t spoke since the break up, it’s been 5 months. He recently got back in contact with one of my good friends and brought me up, saying he misses me. I miss him too (he has no idea) but I don’t know if he’ll ever message me again. I had almost moved on and now i’m back in square one. What should I do ladies, it’s messing with my head