What if they're rather romantic- kissing perhaps?
What if you didn't end on bad terms and really.. the pictures are rather gorgeous and make you happy to look at...
If you were my new boyfriend, would you be uncomfortable with pictures of my ex in my room?
edit: Okay, what if I had spent hours over a big photo collage and framed and hung it on the wall.. the pictures were of my time travelling and he was in all of them because we did it together, but it also shows my time away so it's not dedicated to him or anything. Do I have to take that down too?