First, I'm going to say that your fetish is perfectly all right. And I think that opening up about it in your relationships is exactly what you need to do. 

Second, I'm going to suggest that if your therapist, regular or sex therapist, is making you feel "judged," that they are not a good fit for you.  It isn't that I don't think the sex therapist is good at their job, but that therapists are rarely "one size fits all."  I realize that trying out different therapists can be difficult when you're constrained by a health insurance plan, but I would encourage you to try different therapists until you find one who is a good fit. Unfortunately, there are still a large number of mental health professionals who find fetish in all of its forms distasteful, and are not shy about displaying that bias in their treatment of the kinky. 

As for finding friends, lovers and playmates with whom to engage in your fetish, you have to be willing to ask for what you want.  Trust me, I know it is difficult to ask for kinky things, but the first step to that is recognizing that there isn't anything wrong with it.  You're not hurting anyone, particularly with your fetish. 

I remember how terrified I was the first time I asked the then future Mr. Strangiato to tie me up and whip me.  We'd only been dating for a little while, and as it is something I knew I wasn't going to be happy in a long-term relationship without, I knew I had to talk to him about it.  I packed up my little bag of tricks and went over to his place.  So, I do understand how difficult it is to open up about kink.  Even though we share a great deal of our kinks in common, I still have things I hesitate to ask for because part of me still fears that he'll think I'm a sicko, freak weirdo. 

I would encourage you to explore the fetish community in your area.  For example, if you're in the Seattle area, check out the Wet Spot (http://www.sexpositiveculture.org/), or as I believe it is currently called, the Center for Sex Positive Culture.  They have social as well as fetish events. 

Once you have met some people through your local fetish scene, I think you'll have better luck finding people who are willing to indulge your fetish, and even some who share it.  I could write a treatise here on why people react so negatively to alternate forms of sexuality, but it would probably get real boring real fast to everyone but me and about four other people.  The fact remains that an awful lot of people view anything outside sexual "norms" as threatening.  However, most people who are comfortable with their own kinks and sexuality are generally pretty comfortable and not threatened by the kinks and sexualities of others.  So, the fetish scene is probably your best bet. 

Now, I have a question or two:  Are you capable of having/enjoying sex without tickling?  If you find a partner who is willing to indulge you in return for your indulging their fetish on an equal basis, do you think you'll be able to reciprocate?  If the answer to these questions is "No" then I would most definitely advise you to find a different therapist, one who is used to dealing with the fetish community, or who is at the very least neutral toward fetish.  As I said before, there are still quite a large number of mental health professionals who are biased against fetish.  The easiest way to find "fetish-friendly" counselors and such, is, again, to explore your local fetish scene.  I know, for example, that the Seattle scene is incredibly chatty about these sorts of things. 

I, personally, would encourage anyone who can only achieve orgasm through one form of stimulus to seek counseling about it. Granted, that's just because I'm all about exploration and variety.  However, if you find someone who shares your fetish, and is more than willing to join you in it I think that becomes less urgent. 

I hope this has helped. 

-Valerie