Help dealing with partners difficult child

[Runcyc]

First thing I should say is I'm a man. I'm not sure if should even be on here but i'm just looking for some advice don't really know where else I can get any.

Been with my partner just over a 16 months but we don't live together. The issue is her 16 year old son and his attitude/behaviour. Ever since we've been seeing each other his behaviour has been bad although it started before we meet and he's never been rude to me. He regularly swears at her using any and all language, says he wishes she was dead and will go mad at anything she asks him to do, even just giving her his dirty washing etc. If she turns the internet off late at night because of school he'll go mad take her car keys or something and refuse to return unless it's turned back on etc. My OH has a daughter who's 18 and really nice but the son hates her too. Mother and daughter are close which I wonder could be something he doesn't like. I should point out the ex husband doesn't want any confrontation with the son and so won't try and back her up in anyway even when the son is rude to him.

I've somehow bitten my tongue in front of the son which i find hard but need to do. Unfortunately when it's just the 2 of us I do say more of what i think and how he needs to be disciplined (yes i understand i shouldn't of) Apparently he's being worse than ever (her words) atm and so she'd rather I didn't come round because she says "I know you hate him!" I'm old school and you always respect you mum

I don't want to loose her, we really are good together. I just hate seeing him upset her and I want to change and help her on this rather than cause her more stress. Any advice on what to say to her that I really do intend to change (I do) and any practical help on what if anything I could do to mediate or help her would be gratefully received?

I would think that if your girlfriend asks you to mediate then you do and if she asks you to stay out of it then you do that.

However, what is her take on all this? Why does she let her son treat her like this? What do you think of her parenting generally?

She just seems to think it's a part of growing and he's having a tough time, he's bright and school is hard.

She is quite highly strung, is stressed a lot, suffers from a bit of depression and just doesn't like confrontation. Usually she just gives in to get peace and quiet for a while but obviously he knows this and will play on it. He's a big lad and although he's not been physical his size intimidates her I think.

She's a great parent, loves them both unconditionally obviously will do anything for them. But her and her ex have just totally mollycoddled them over the years and neither of them can or will do anything for themselves. She drove 6 times in one day a few weeks ago dropping and picking them for different things, total distance around 4/5 miles which to me is crazy

I have a similar thing with my girlfriend and her total brat 13 year old daughter,who adores her total swine of a Father who still makes gfs life difficult. GF is really sweet and good-natured,but is so soft on the daughter and 12 year old son that I don't see it changing any time soon. After 2 years of being nothing but generous and polite to both kids Ive decided to just never be there when the kids are around as I cant bite my tongue any longer,and if I get involved it would inflame the situation and Id then become the scapegoat for their awful behavoir. If you dont live together then just avoid the kids as much as possible,theyve had that relationship a lot longer than youve been on the scene and your input probably wouldn't help much.