Who said it was a random person?

I supposed it. Probably because I would not call them 'someone' if I knew them. I would call them if not by their name, at least in some distinctive manner: my spouse, my parents, brother, sister, aunt, neighbours, friends, colleagues, whatever that would make them be more specific than just someone. I may be wrong, indeed.

But I should have it made clearer that I would also not care much, I mean I would not be upset or worry or whatever, if anyone I know was suddenly to decide they don't like me. Except from one person, my spouse.

I am old enough to have seen a lot of people come and go out of my live, and me go in and out from theirs. That's fine.

If anyone I know or I am in contact with was to tell me they don't like me, I would...

1. First, I would try to think why they wanted to say that to me since it's very... not friendly and very much not the way adult people are supposed to behave when meeting one another.
2. Then, if I can't find anything I have done wrong that would explain their feeling towards me (and that should be something I would want to change too), like suggested, I would move on. Having already considered what I may have done wrong and supposedly found nothing or nothing that I would want to change if I could, why should I waste more of my time about someone's else feelings toward me?

We would probably see a lot less, if at all, since I don't need many people around me to feel ok and since I don't see any reason to impose myself where I'm not wanted. That's the most likely thing to happen, that and me making a note of it in my journal if I think it's worth noting.

Edit: typos.