My insecurity is not my partner's responsibility. It is mine.

For example, if my insecurity is what made sex absent or unfullfilling in our relationship then my partner going online is in great part my responsibility. Yes, he did not have to do it. Yes, he could have accepted becoming celibate, so as not to make me feel bad. He could have been satisfied with self-pleasuring in a shower. To make everything about MY insecurity is a bit selfish.

But also I can see a scenario where this partner staying at home all day, is a man, unemployed, who can't find a job, who maybe gave up on trying to find a job, who has nothing to do, has to depend on his wife or girlfriend's job to live. He is depressed. He is feeling majorly inadequate and a failure as a man, and he is trying to make himself feel a bit "manly" by engaging in this online sex, even if it is an illusion. If that's what's going on here, no matter how insecure I am, this would not threaten me, this would make me feel compassion for him.

I don't know what's going on. I think it's a good idea to find out, before taking the high road.