Partner only nice when...

[Redfronts]

Daily I have recently noticed him trying to chip away at me for any reason. But when the evening comes when we can have sex, he suddenly becomes very charming and jovile. Tonight I have refused and explained my reason to which he has thrown a strop. I’m starting to think he has narcisstic tendencies. Anyone else dealt with this in a relationship?

Conditional niceness (ie on,y nice when there is something in it for them) can be a sign of someone who has narcissistic tendencies. You would see other behaviours too. Worth reading up on the indicators or people with npd. He could also be emotionally abusive without actually being a narcissist as many people have some narcissistic traits and tendencies without actually being a narcissist.

And whatever the reason don't remain in a relationship with someone who treats you badly and sulks to get their own way. Don't fall for the sink costs fallacy or remember the person they used to be and think that person will reappear. Lots of abusive people show an entirely fake persona to draw you in before revealing the real them.

He isn’t nice.
You should break up with him.
HTH.

What red said. This is who he is.