A lot of people have trouble flirting even without a stutter. The real answer is just to try and be willing to fail a few times. I know that sounds fake and impossible. As far as people who've said might find your stutter cute, its alright for it to be offputting, however you should also think about it from their perspective. It's a big assumption on your part to think someones belitting you because they were trying to be enthusiastic about something your friends probably forwarded about you.