On the hotel side, Marriott (at least) will let you combine accounts up the the amount needed for an award. So, if you have 100K in your account, your wife has 50K, and you want an award for 135K, they will take the needed 35K out of your wife's account.

In general, outside of the now-defunct Mutual Account with Hilton, most hotel and/or airline programs do not allow you to pool miles/points, even with spouses. BA is a notable exception, and the members of your household account (up to 7 now, IIRC) don't even have to be related -- just residing at the same address.