I don't know about you, but me I'm a very "routine" person. I get used to the part of town where I live, to my neighbours, to the supermaket, the vet, the video club, everything around me, even to the traject I use to go to the gym. Moving is not just about being more far away of your friends and family, it is also the loss of familiar habits and sensations. I would be very nervous too and, of course, when I'm nervous, I cry a lot...
The other thing that would make me feel nervous is the fact of leaving everything behing to go live with my boyfriend. I now live with him and I don't regret it, but at first it is hard because it meant that I was much more engaged in the relationship and therefore much more vulnerable too. I don't know if you have ever lived with this boyfriend before but if it's the first time, it's perfectly normal to question yourself a lot, to feel nervous and to get sad. Only thing I can say is that, even though I had to acclimate to so much new things and even if I cried a lot wondering if I had made the right choice, I don't regret having the guts to do it (to me, it took guts, I know that it's more natural to many other people). I wouldn't be happy like I am now if I didn't have the courage to try first.
Good luck and I hope you will find what you really want. Once you know it, wether it's staying where you are or making the big move, you won't regret if you listen to yourselt. You might feel anxious again and cry again, but you can't regret listening to what your heart has to tell you.
I wish you get better.