How would you react to a gay person who found you TOTALLY repulsive ?

[Pyrrho]

In this sort of case, one typically can completely avoid dishonesty and just not say anything about the appearance of others.  I usually do not go about offering my opinion on the appearance of others, regardless of whether I find the person attractive, repulsive, or indifferent.

If you meet someone like him again, you might want to memorize this phrase to respond to any unprovoked crap from him or her:

"If I want your opinion, I will ask for it."

I agree there's no reason to say anything if you feel indifferent or repulsed, but I can't deny I do like to flirt which requires saying if I find someone attractive. But as I've said elsewhere, only among friends, and only if I think it would be welcome. But if someone makes it clear that they don't want to know either way, as you have and others have in the past, I totally respect that, and wouldn't go there.

Unfortunately, with the brutally honest, your recommendation doesn't usually work, for me anyway

It may take more than once for it to sink in.  But repeating, when appropriate, "If I want your opinion, I will ask for it," will likely eventually convey the right message, unless the person is a complete moron.

Also, when socializing, you may wish to be more exclusive than some people, and exclude people who annoy you, regardless of why they annoy you.  I have been rather amazed at what some people do, who willfully socialize with people and then complain about their habits later.  If their habits annoy you, why socialize with them?  It is one thing to have a coworker who annoys one, as then one often does not have much choice, but on several occasions I have encountered people who choose to socialize with people who annoy them.  If you choose it, you have yourself to blame, when it is something that is a repeated habit.

Usually, when I point this out to people, they respond with "yeah, but..." and then say some lame bullshit nonsense.  If you choose to be with people who you know will annoy you, you are to blame for your choice.  If it is forced on you (like an annoying coworker at work), that is, of course, quite a different matter.  But many people choose to socialize with people who bother them.

This also applies to romantic relationships and is not merely a matter of platonic ones.  I remember talking with an acquaintance who was complaining about her boyfriend, who, from her description, sounded like a worthless jerk.  I told her to dump him.  She said, "but I love him!"  If one chooses to be with people who are worthless jerks, one should expect to be annoyed by it, and one has chosen it, so one only has oneself to blame.

If you put up with crap, you will very likely have crap to deal with.  Dump the worthless boyfriend/girlfriend/friend and you do not have to deal with their annoying crap.  Choose to be with them, and you choose crap, which is your fault.