My closest friend does a lot for me too. She's helped me plan my finances, clean my house, looked after my kids, painted my toenails etc. Her husband has occasionally been jealous in the past but it he settles when his wife gives him extra attention!
I used to be the one that looked after her, not so much in a practical sense, more that she relied heavily on me for support and to help her get her life sorted out when we were younger. Now the support is more even, but as my marriage has faltered she seems to have found other ways of helping me out. This is what friendship is all about, in my view, sharing the good times, helping each other through the bad. All my close friends give a lot. I never thought it was that unusal but lately many people (acquaintances/family) have commented on it so maybe it is.
Stoneheather, what he said is kind of insulting but I'd avoid confrontation with her husband, if I were you. Her marriage is central to her happiness, as are her friendships. She needs to find a way for both to continue.