We took my MIL about 5 years ago for her first trip to WDW and stayed at the WL (Grand opening week). We did a top notch vacation for her (she recently retired). Well, the day we went to MK was Gay day (week). Being a flight attendant (at the time) it didn't bother me at all since I worked with many gay people (they are just as pleasant or not as anyone else). My MIL was horrified!!!!!!!!!!! My DH and I just laughed our butts off! There were alot of gays and lesbians, as far as numbers go, in the thousands. We didn't see much "kissing" among the couples, which pleased me because my 2 year old DD was with us, but there was alot of hand holding, which doesn't bother us.
All in all, if you can get passed the fact that these people are gay, then you will be o.k. Chalk it up as a lesson in life to be learned. There were not outbreaks or riots. It was just like any other day at Disney (with a large crowd) and just a little less families! All in all we still enjoyed ourselves.
If you are bothered by the presence of gays, then use the weekend to relax and hang at the pool or try another park. Maybe a CM can direct you about which park is being utilized as gay weekend?
Don't let it spoil your trip.
Enjoy