First of all, I doubt that you are imagining the mockery and ridicule. It's trite, but there are plentyof people in the world who suffer from such a degree of insecurity that they feel empowered by mocking and ridiculing the odd; the different. There are also plenty of people who seem to be incapable of empathy even when face to face with suffering.
Unfortunately these people are simply jerks (to put it mildly) and mockery and ridicule is seldom a response they must experience themselves.
While the advice you have received to ignore it is essentially good, it's obviously not a simply task, as you've undoubtedly found. I would not be surprised either to learn that when faced with mockery and ridicule some of the behaviors and mannerisms that give rise to it are intensified.
My suggestion is to think about this: While the people who ridicule you may seem to be in a favorable position due to their numbers, anyone with decency (and most people have such decency) will find their behavior despicable, and even if they don't have the courage to tell these fools what they think of them, they think very poorly of them.
This is precisely what most of those who mock you fear and so take heart in the fact that not in spite of, but because of the way they treat you, the reason for their insecurity is confirmed. They have proven themselves to be the jerks they do not want to be thought of as being.
I suppose it's questionable whether or not anyone deserves to be mocked or ridiculed but certainly if anyone does it is the bully who torments the odd duck in the flock.
Having said all of this, it hurts to be ridiculed and even more so on a constant basis. I would suggest you ask yourself if any of the behaviors for which you are ridiculed might legitimately be considered offensive (for example: getting very close to someone when you converse and repeatedly touching. This is not to say you do this but this is the sort of behavior that most people find very uncomfortable and which would set the person who engaged in it apart as odd) and, if so, see if you can restrain yourself (again easier said than done, but you have asked for advice)
If, on the other hand, you are being ridiculed because of harmless eccentricities then I wouldn't encourage you to change your unique ways.
It would be very unlikely for your therapist to express anoyance with you, let alone hate you, but there are bad therapists just as there are bad lawyers, policemen, and presidents. If you feel this way about your current therapist, then I urge you to find a new one. However, if you find in short order or even over time that the new therapist is annoyed with or hates you then I would urge you to discuss your feeling with the therapist. It would be very unusual for you to get two really bad therapists in a row.
As far as this forum goes, don't take anything anyone writes to heart. We are faceless, nameless beings here and this is not a place where empathy abounds. This is not a criticism of anyone here because we only know a fraction of each other based on these posts, and there is no reliable way to see people beyond the words they write.
That you are seeing a therapist is an indication that you feel you need and want help. This is a good thing. Stick with it and try not to give the jerks who ridicule you power over you. Get a little bit mad and determined and think "The hell with them." Everyone can't be your friend and you don't want to be friends with everyone.
Hang in there.