Your problem is that you lack confidence and self-esteem. There's nothing wrong with being a bit overweight; and your boyfriend is still with you, right? So I don't think it's a problem for him. If it's a problem for you, try to change your diet and exercise, so you can lose the weight. But even if you do, you still need to work on your attitude towards yourself. Some guys like to watch porn alone, but I do think it's nice that you try to enjoy it with him. I think you need to learn to like you. You're worth love and deserve happiness.