Lots of stutterers in the world along with you, friend. Even more people who have been rejected by romantic interests. Many repeatedly! Focus on yourself and beating back every voice in your head that says you can't do something. Love interests come and go. Everyone goes through that. It's probably better for your mental health to reduce contact with her. I personally can't continue close friendships with exes or people who I was interested in. On to the next one, even though it's difficult now. Good luck. You've got a whole lot more life to live and way more to experience.