What, if you don‘t like people (no more)?

A question, that strikes me from time to time – without any clear reason.
If you recognize, that you don‘t like people or you don‘t like them no more – what do you do? You continue engaging and trying to find a way to like the respective people? Or do you disengage, just state the truth and act accordingly?
At the moment, I am debating this with myself and my partner to an extend, that it annoys me. I am just spending too much time thinking about how to deal with this or that person. Instead of just embarrassing it and live along these lines. Means – if you really know that you don’t like somebody (no more), just walk away in a proper, but clear way and don’t make a too big fuzz about it. Better to clear your mind, better to be honest. And don’t bother, if you just don’t like somebody – this happens!