Good advice!
I would say, ask her how you can help. Simply say something like, I love you very much and I support any positive goals you have and will help you any way I can
That should do a lot. My husband is very good about staying out of things -- he doesn't criticize if I slip, and joins in when I am proud of myself (me: I lost 3 lbs honey... Hubby: WAY TO GO babe, you're awesome!)...he will also tell me randomly that I am looking really good or he can really see the difference in my face or whatever.
The key is, another poster mentioned -- he doesn't at all police my food or make comments regarding that. It isn't his place to comment, in my opinion. If I talk to him about it, as in, "I am so disappointed I went over my calories" he is encouraging "don't worry, one day is not what makes or breaks it...I know you'll do great tomorrow, don't give up!" stuff like that.
Good for you for supporting your partner
I love coming here because then my weight loss efforts don't become the entire subject of my marriage like can easily happen when some one is very committed to a cause