I’m insecure. My boyfriend watches porn

I recently found out my boyfriend has been watching porn. He has been lying saying he doesn’t. Probably to save my feelings. He has sexy photos of me and says he uses those but sometimes he wants to look at other women. They have beautiful bodies and sometimes my pics alone aren’t enough. Of course I feel insecure now. I told him to stop but according to your articles that is not something I should do? I’m just so confused and don’t want to be lied to over this. But it is hard to be ok with him doing it. I feel like he should only see my body. What do I do?