So from what I've experianced - everyone wants to bang.

I initially kept Sam Coe around because he's handy with a gun and I was waiting to meet Andreja. But I swear the entire time he was giving me the fuck me eyes and I'm like no dude thats not cool lets just be friends and then I go to Barret later and he's like "Oh I'm so lonely" and I'm like then start a dating profile I am not an option and then Sarahs like "Hey BTW I'm single but I have these issues" and I'm like NON OF THIS IS APPROPRIATE FOR THE WORK PLACE.

From what i experienced with the 4 companions, yes, immideately after finishing the companion quest and having the romance option, the commitmemt option opened up

I have only gotten a few flirt options, nothing past that. On my second character since my first one’s main story broke. Do you know how long you keep your follower before they care?