Don't be so hard on yourself. There is no right or wrong answer. I think an e-mail is a good idea...it's in between no contact and a phone call.
I don't think you're at a point where and e-mail would push her away...but that's just my opinion and I don't want to steer you in the wrong direction.
Good idea to sleep on it (and pray on it) and see how you feel tomorrow.
J~
M 35 H 29 M 4 yrs T 9 yrs D 3 S born 10/19/07 Bomb 09/10/07 Separated next day OW - broke up and H moved out 09/07/08 Status - still figuring this out