Just what he wants pp, to be piggy in the middle between op and his 'oh so evil and controlling gf that he can't seem to leave' when in fact, he is the puppet master. Pulling all the strings and then sitting back to watch.
Please try and think of the poor partners perspective.
I'll give you an idea of how it goes living with a narcissist (which I suspect,he might be). She meets a guy, he seems just perfect, its a magical whirlwind ride (love bombing). They soon end up in a relationship and for a while she is so so happy. But then, things start to change. Just little things at first. Like, he seems 'off'...and then, little criticisms start to come in. Like, he doesn't like 'that new shirt of yours' or 'I think you'd look better as a blonde' (meaning: I dont like you brunette) and then gradually, worse things. He tells you your friends are sluts or family don't have your best interests at heart. He withdraws physical affection and implies you are too needy. But he starts to demand more extreme acts in the bedroom and if you aren't OK with them, you're a prude.
You call him up on some of his behaviour only to be told that you are the one with the issue: why are you so over sensitive/nagging/crazy/controlling
ect...
...'am I? Am I those things?'.
He tells you things and does things and then five minutes later, denies saying and doing them.
His phone constantly beeps whilst he us sat on the sofa next to you, ignoring you. Because...well you dont know, but you must have done something wrong...right?
He starts talking about his awesome friend who is so cool and has great style. 'You should dress like her' he says.
Eventually, you call him out on it. He says 'she is just a friend' or 'she texts so much because she is obsessed with me, what can I do?' But, he doesn't block her.
Ultimately one night, upset, lonely and stressed out if her mind she decides to read the messages and ask the girl what us what herself. She feels shame going this and knows it will be held against her. He will punish her tenfold by stonewalling, shit comments and cruelty. But she has to know.
She sees he has been slagging her off to another woman. And heart breaks just a little bit more. She didn't even think that was possible. Where is the man she dell for? ...Why isn't she enough?
Get the jist of what might be going on now?