Just keep the lube in the nightstand. You can't just reach over and squirt some in your hands? Or, in her hands and let her apply? Seriously, buy the good stuff and just put it in the drawer. Don't get caught up in orchestrating a perfect session. There is a certain hotness in a man that handles the lube (and, in some cases, condom) in a matter-of-fact, "taking care of business" way.
How the heck can you perform with logistical worries in your head?
The length issue, I understand. I imagine she prefers being on top so that she can control how deep you penetrate. To keep it from getting boring, and to earn her trust, maybe you can practice other positions just a minute at a time (promise her it will only be a minute and keep your promise unless she wants you to keep going).
I just noticed that Babeland (my favorite sex store) no longer carries Slippery Stuff. I called, and learned that they reformulated and replaced it with their own brand: http://store.babeland.com/safe-sex-lubes/babelube. The lube has a thicker consistency so it doesn't pour all over the place, odorless, tasteless, stays wet a long time, free of parabens and other stuff that irritates. I trust these people. They know sex.
Your sentiment for coming here is touching. I'm so glad she stayed, and I'm so glad your marriage is in such a healthy place of growth.
