Friends for around eight years. Our friendship worked well on a superficial level but as we have become closer friends I’ve noticed a lot of red flags and generally toxic behaviour. Loads of examples I could list, but a few of the main ones are that she NEVER seems genuinely happy for anything good that happens to me, and actually seems quite bitter about anything good in my life. The few times I have shared anything difficult I am going through, she seems to be intentionally insensitive - having money issues and she bragged (within the same conversation) about having disposable income and how she was so glad she wasn’t in my position
and similar things like that. Loads of examples I could list. 
I’ve reached the stage where I don’t think it will be beneficial to call out the behaviour, because it happens in most of our interactions. The friendship feels very one sided - I have helped her lot with her career with areas I’m knowledgeable in (I am a bit older and we have worked in the same industry) and her personal issues, but I never receive any support back from her when I’m struggling or need help with anything. So I’ve started to realise she is a bit of a user.
She has also always copied me which is not a huge issue but getting more irritating - recently she has pretty much recreated my social media posts - same photos and very similar captions - and she is constantly asking questions about my life, and has been copying lots based on my responses. (I stopped telling her anything as soon as I noticed!)
Another thing I’ve picked up on is that she is very negative and unkind about other people she is close to - and has shared very private things about their life with me. So it makes me uncomfortable and as if I need to watch every word I say around her, as it’s likely to be repeated.
So all in all I feel like our friendship has run its course and is becoming a negative. She isn’t the sort of person who would be able to have a mature conversation about these issues and respectfully end the friendship, I know it would get nasty this way (she seems to have some narcissistic traits). I’ve toned down our contact, but I’m not sure what else I can do to speed up the end of the friendship - I’m looking forward to the point that we have no or minimal contact! Any advice welcome, any previous friendships I have had have ended naturally by drifting away, so I’m not sure the best way to go about this. Tia 