read right as polite, because they get offended easily.
I’m a male nurse in a predominantly female unit.
How I see a job: I'm there to work and go home and don't want to socialize. Each of my coworkers is welcomed to talk about work with me, but I don’t disclose my personal life, age or life goals with them. Work and let me work. If you need help, call me, we’ll work together.
How my unit works: there is a group that’s childish and gossipy, don’t know boundaries and act like a clique, but maybe 50% of the unit are people that work and let me work, help me and I help them (with the gossip clique this is not always the case).
I was sick for 4 weeks and I’ve decided this is a good opportunity to establish boundaries, something I’ve never done at my current unit. Why now? Being sick I had time to think what I don’t want in my life: faking interest in the sexual life or my coworkers, knowing who started dating who or what they think of Biden or the second amendment ain’t things I care about. I’ve had a coworker trying to find me a girlfriend a week after knowing me. No thanks.
I'm entertaining other job prospects and I still don’t know if I’m gonna jump ship, so for the time being, I'm here. Where I work I’m forced to eat with the rest of the team, including the gossips, so I’m trapped (because if I don’t eat with them they’ll start asking why I’m so unfriendly or if I’m angry at them and feel offended, they simply cannot understand that sometimes I want time to unwind without them).
What I think I could tell them, next time they start with their inquisitive questions:
‘I’ve worked here for a year already. It should be clear by now that I’m not a talkative person. This is a question I don’t want to answer. And I hope that you respect that.’
‘that I don’t talk doesn’t mean I hate you, it means I have nothing to say’ < I find it ludicrous even having to explain this.
‘I don’t see what that has to do with the job’
‘I don’t talk about religion, politics or my private life with coworkers and I hope you respect that’
should they keep pestering:
‘all right, I need time to unwind, which means today I’ll spend my pause somewhere else.’ and proceed to eat alone somewhere else.
And if they pester yet again:
‘leave me alone’
if by this point some of them start giving me the evil eye and afterwards start ignoring me or treat me differently, time to accelerate my transfer to another unit.
If you like keeping boundaries with your coworkers, what do you tell them that works?
I work with nurses. The vast majority of them are lovely people, but I've seen the nurse cliques you are talking about. So has my wife, who also works with nurses. I've seen departments of nurses with that "mean girl" vibe that require long-term HR intervention because they are so toxic to one another.
If you see this kind of behavior, run for the hills. However, if you are just talking about normal human interaction to pass the time and socialize, then it is you who are not conforming to normal social expectations. You don't have to conform, of course, but there are consequences to being anti-social.
The question is, are you an introvert or a misanthrope? An introvert needs alone time to recharge and that's fine. A misanthrope doesn't like people, no doubt because of some childhood trauma. If the latter, then therapy might help.
If you truly are an introvert who needs alone time to recharge, I'd suggest "going home to check on the dog" during your break. Even if you don't have a dog. The point is that you need alone time and that's perfectly valid.
If you are generally sociable, but simply find their particular conversation boring or insipid, I'd suggest training for something where the work culture is more professional. Regular hospital floor nursing almost always has a "break room culture" and it is easy to get trapped in it, but there are lots of alternatives. Learn surgical assisting, for example, or become a nurse practitioner. Street nursing, public health nursing, and home care nursing are all examples where there is no real break room culture. Or get into management, where there are no breaks.