Are you jealous of your bf's ex wife? ?

i mean she was fat and not that pretty and i just keep thinking that he is always thinking about her. in our apartment there are still stuff of hers. he won't let me throw them away. he keeps little things of her, like an old cell phone that she got for him. just little knick knacks that sometimes drive me crazy looking at it. am i the only one. he doesn't have any pictures of her. they never took any together.