I'd appreciate some advice as this is really getting me down and I'm not sure how to deal with it. I don't want to end up accused of bullying or anything like that but it's making me v depressed.
I've been in my current role for two years now. Originally a team of 5 and 3 have left in the last year mainly due to a restructure that expanded our team to 7 people, some getting new job titles and roles, and some (including me) getting pay cuts.
Anyway a colleague is now my manager and there are 3 new staff in my team. None of whom have the specialist skill I have and which was part of my previous job title.
Anyway they are contacting all my old clients and repeating information and activities that I've been doing over the past two years and this has led to confusion on the part of the clients and I just feel it is disrespectful to not even check in with me what has been done previously.
Some clients are still my clients because their work covers many geographical areas (each member of my team has a region - I used to be nationwide). So again this means they are being approached by different members of our team.
I tried to create a spreadsheet of engagement to avoid duplication of activity but it's being ignored
I am now getting defensive and snippy emails from one member of our team simply because I pointed out that the situation with one client is particularly sensitive and I had been handling it for the past two years and was probably best to continue doing so. She thinks it's time for "new people and new ideas" and that she has "a long background in this field@. So do I sweetheart. 
My manager said st the restructure that she didn't want me to feel pushed out (I do) and that my previous experience would be valuable and used (it isn't)
I do have mental health problems which my manager knows about (she has some too) and this situation is really affecting me but I keep getting told to be fair to the newbies
I'm looking for other jobs but as it's public sector I get paid way more here than I would elsewhere.
I don't know what to do and would appreciate advice. This colleague I think is quite sneaky and I wouldn't put it past her to accuse me of bullying so I'm trying hard to keep my mouth shut but it's not easy!