Wow, that sounds like a big skin tag. I get small ones on my neck. Ask the OBGYN if you can have it removed or be sent to some specialist, especially since it's causing these issues.
Usually what they do with skin tags (DO NOT DO THIS YOURSELF) is to wrap a string around it to cut of the blood supply and cut it off. I say not to do it yourself because where it is and how big it is, it's going to hurt without numbing medication and probably bleed a lot. Also, the location makes it vulnerable to infection, which could be very bad.
I hope you find a doctor that can remove it. Best of luck to you!