what would you do ?

nothing as long as i properly close anything from my ex gf........

lol i have actually been in that situation once, long story, but it is uncomfortable to be affectionate when in the presence of the ex. There were no problems though, i just felt lost on how to act at first. After a while i acted no different than i normally would, there were never any arguments, or any hurtful things said. It was really weird, and i would hope that i am never in that situation again.