It is an unfortunate thing that happens, but it shouldn't stop you. Just like when people write mean derogatory comments on regular videos on YouTube, and those people continue making videos. There's always going to be creeps, mean people, etc. But I've learned early in life that if you make decisions on what you do because of what other people say or do, then you pretty much are giving them what they want.
So by all means don't let someone creepy stop you. Or even better, point them out on their creepiness, sometimes people don't know how something sounds to another person when they say it. A lot of times, people (usually men) get uber-excited when they see someone else (usually a woman) shares a tickling interest, and just automatically assumes tickling will take place and they can be as direct as they want tickle-wise.
But just because you have a similar interest doesn't mean you are going to feel comfortable having some stranger say "I wanna tickle you all night long" (which, news flash people, if you do that to someone, they might die, and then you'll have other problems on your hands 🙂
And just so you know, it can happen to all of us. I had an experience back in college where a man from another state that I still to this day do not know found my personal info through an online directory and mailed me a letter in graphic detail about how he wanted to tickle me, even though I have never online shown an interest to participating in m/m tickling. I wasn't even a member of the forum yet! That could've been enough to stop this altogether. But now, I've even some nice, normal, respectable people in this community that I wouldn't have if I would have let one creep stop me.
I've even gone to dungeons where the ladies there have complimented me on being "a genetleman" with them. Even paid people aren't fans of creepy!
Hope my rambling helps you get past the weirdness you might feel and helps you be more comfortable interacting with the community. You may have so swim through some strange, but you could end up meeting some cool friends. Hey, I might be one of them! 🙂