I was on the flip side of this (I was the nursing student with husband who is a nurse). I can tell you this much from my perspective...my husband was a more valuable resource than ANY nursing book. He provided encouragement when I was struggling with the stress of an acclerated program. He provided feed back on my care plans without giving me the answers. He was a great sounding board. I don't think I could have done it without him and I hope that I let him know every day what a treasure he is then and still is in my nursing career today.
I know it can be stressful watching someone else go through nursing school after having lived it yourself. But since you didn't have a "you" to help you through it all, take advantage of this opportunity to use your nurse mentoring skills in a very relaxed environment...give him some constructive guidance, show him other ways to look at things as he develops his care plans, be that non-critical sounding board as he talks his way through what he's learning.
And make sure he takes you out and treats you to some non-nursing school related good times!