I definitely agree with Mark. Have you started any counseling yet?

You may feel guilty, but, again, she is just as much at fault in this situation as you are, and I still think you’re doing a disservice to her by keeping this going, especially when you know it’s eventually going to have to end because you aren’t going to want to do this for the rest of your life.  The longer this takes you, the more she’s going to cry…. rather than just crying through her feelings of the breakup until she gets over it, she’ll cry every time you guys fight and then end up crying through her feelings of the breakup anyway when you’ve finally had enough. What you are doing now is just prolonging both of your suffering, so if you haven’t started counseling yet, I’d really, really suggest you do so and work on developing the strength to do what you know you need to do.