Hello Ladies, I could use some of your womanly wisdom if you have a moment.

Background: My SO and I have been together for 4yrs.I'm 27 and he is 31. Every Christmas my SO gets quite upset about his relationship with his mother. She is the classic example of a narcissist so their relationship is tenuous at best and it always has been. His dad passed away a few years ago so there is no one else who understands her behavior like him.

Issue: Each holiday he tries to repair relations, by getting her to apologize for being the way she has been and to put effort into being a better mother. Each year for the last 6yrs it hasn't worked. Her response is he needs to just forgive her and find Jesus. I try to be supportive of his efforts but my support doesn't come off as genuine because it isn't. The last 2 years I have tried to gently say it's not worth the trouble, maybe cut contact, clearly you care more than she does, etc.

So far I don't think it's done any good and I think I should just be supportive with whatever decision he makes but it's hard when I see him literally lose sleep over it.

Should I stay the course? Stop having an opinion about a relationship I'm not part of? Any insight is appreciated!

Edit: thank you everyone. I will remember your words and be supportive. You're the best sounding board when I have none.