NC for this as really outing.
My manager recently returned to the job after leaving for a short time. We got on fine before she left but since she's been back she has taken a very vocal disliking to me.
Every time we speak (1-2 times a week) she has something negative to say, usually along the lines of repeating some issue a senior manager has with me - never related to my work. I have my doubts as to whether any of it is true as the senior managers are usually very nice to my face and think it may be coming from her but she wants to make me feel ostracised from the team in the process. I have no issue taking constructive criticism but think it is verging on bullying as it's every week and not really related to my work, which they have always been happy with from what I've been told.
This has all come to a head as I requested flexible working, which other members of the team have already been given and I have a genuine, unavoidable reason for. I have been told no because then 'everybody will want it' - except others already do have it.
I made it clear I would have no option to stay in the role due to this unavoidable situation and said I wanted to try and find a solution so I could stay at which point she said, 'Why don't you just become a housewife and never have to work or leave the house again'. 
I then received an email from her to let her know if I'm leaving - all with a very passive aggressive tone.
One of my colleagues has noticed her odd behaviour towards me and in general and is urging me to go to HR or her manager about it as she thinks the housewife comment alone is completely unacceptable (no offence to any housewives) but I think it'll be the end of my time there and I really loved the job until she came back with this new attitude. WWYD?