Brother in Law acting up...

So there have already been issues with my Love's brothers making moves on, dating, and sleeping with his exes and whatnot...so this is a pretty touchy subject because I have no idea how to perceive or handle this.

My brother in law hugs me every time he sees me, which isn't an issue. They all do & I love em as brothers for that, BUT this one brother in particular makes me nervous sometimes because he hugs me different when we're around others and not. When we're around others he'll hug me around the arms or right underneath them and pat my back, usually looking else where. When no one else is around his hands are always a little lower and he gives me a peck on my neck. Well, actually no. That's why I'm asking all this. See he popped up tonight, while my lovey was out, and that was his first time doing that. Usually its a pretend kiss by the cheek, but this one was square on my neck & I just kept it moving to figure out why he was there (borrow some movies...) and played it off. I'm scared to tell my lovey. I'm not trying to see them fight..

Maybe I'm just over thinking all this?