Disorder that stops me from holding guys hands

I've got the same condition with my hands. I find it's always best to confront things you're embarrassed about head-on rather than trying to hide them as it just makes you look like a weirdo, whereas if you just address them then it's not embarrassing or weird anymore. So I've always just said to girls something like "I get really clammy hands, so I totally understand if you don't want to hold hands with me!", they always just laugh it off and say it's fine.

I have hyperhidrosis on my hands so my hands sweat massive amounts no matter what's happening. It's really embarrassing when guys try to hold my hands because I don't want them to get disgusted or something.

I've just started dating a guy and he keep trying to hold my hand but I keep making excuses so he doesn't. I don't know how to tell him without him getting grossed out.