Yeah,here's my 3 different Shepards ract to this:
Sharon,Paragon female and a single: So you're gonna be together? Good for you.
Marcus,Renagon Male,Ash's man: Finally you're NOT interested in me anymore,this is exactly why I rejected you.
Tyson,Paragon black Male,goes with Jack: That's cool man, Now I have a reason why I didn't propose for you in the first place!