very little actually. My last relationship lasted 1.5ish years, and she didn't even know I had a stutter, until I told her. what it does affect is meeting women. It takes a lot to say hey to a random person at a bar, because of the fear you might stutter. Once I get to know a person well, i tend to not stutter at all around them. Do stuff to make your self more confident. How it works for me at least is, the more confident i feel, the less i stutter.