Hopefully they aren't selfies taken during a poke and grope.

I don't think it's inappropriate. 

If he is your old doctor there is nothing unethical or inappropriate about liking a photo. You are overthinking

“Inappropriate”? What are you, 5 years old? Lmao.

You two are both able-bodies, sexually mature adults who have the capabilities to flirt, marry, have sex, give birth to babies, and raise children. If you two choose to like each other’s pics or posts, or flirt, or talk, or anything else, then you’re totally within your rights to do that. There’s nothing “inappropriate” about it!

The only times it’s unethical is for a therapist to sleep with their client, because their client might be crazy or it might be a conflict of interest with the other spouse of the client. But for a regular doctor it’s totally fine long as you’re not married