A senior faculty hates me -- should I prepare to leave? I am a pre-tenured faculty.  A senior faculty in my department hates me.  She has been  very strange to me.  For example, she sent out a dinner invitation for all people in my department.  I accepted it -- she personally approached me and said like you should not come.  Recently I learned that she has been talking about me very negatively like making stories I've never said or did.  Also it is not just her now - a small group of senior faculties do together.  I am in a female-dominant colleage - however, I am very dumb a kind of in female-relationships; all of my best friends and collaborators are male; so I simply do not know what to do.  Anyway now I am ignoring all and focusing on my works.  However, I am very worrying about my evaluation -- is it possible that I can fail in my evaluation/re-appointment for this situation.  Should I just apply for different schools now to leave?
I think it is critical for you to get more information about what's going on.
I do not know what it is like at your university, but usually starting junior faculty is assigned to one or two senior mentors, usually part of the group who supported the original hire. Otherwise, find the person you trust most among the colleagues that help recruit you for this position. You should bring up this topic gently with one of them and see if this is a common issue for others with the senior faculty member and if there is anything you can do about it.
That said, I would not even consider moving to a new place before you find out more. It is not clear that a) the senior faculty member would greatly impact your career at this university and b) there is no guarantee that things wouldn't be worse somewhere else. I would only make such drastic decisions if you have more information. Taking into account how hard it is to find faculty positions these days, I would only consider this step as my last resort.