hairdog, you're getting really close to the truth! So close, I'm sure you can taste it. Tastes good, doesn't it, but with bitter overtones.
You're absolutely right that her pressure is coming from inside herself, from her own fears and insecurities, and also from the fact that so far she's unwilling to face those fears head-on. She has not been willing to confront herself on them. She has not been willing to work through them - she wants to avoid them and deny them. So realizing this, you have a responsibility (born of respect for yourself and your own sense of integrity) to challenge her to reach inside and confront these fears. Not by being belligerant or argumentative, and NOT by pointing out her "inadequacies" to her (she is ALL TOO aware of them anyway), but by gently and firmly standing up for yourself with her and showing her that you respect yourself too much to accept this version of your marriage without trying to explore what it could be. I strongly urge you to read PM - you'll be AMAZED at how it will affect your thinking. But you're close - so close...