Relationship

Do you guys think that there should be privacy in a relationship. Example my boyfriend left his canon camera in my bookbag and I got curious and looked through the pics and saw pics of his ex when they went to Hawaii. Where she was in a bikini and pics of her ass. I told him I went through it and he got mad at me saying I’m invading his privacy and I’m not supposed to do that. He said there are “boundaries”. He can honestly grab my phone and look through it and won’t care. But he gets so triggered. What is your opinion on privacy and boundaries in a relationship. If he would of came at me the right way I would have understood. I know those are old pics. But it’s the way he got mad.