I don't recommend using a debit card at hotels. Merchants are allowed to place a "hold" against a specific dollar amount on your checking account when you use a debit card -- even if you don't plan to use that card to pay when you check out. They're trying to make sure that your estimated charges will be available to them when you check out. It's like this amount is no longer accessible to you -- it can cause people to unknowingly overdraw their checking accounts, because they don't know the hotel is basically "freezing" that amount on their checking accounts. If your hotel is, say, $200 per night and you're staying 7 nights, that's $1,400 that's being "held" (ie, unusable to you!) until you check out. If you assume that $1,400 is there for you to use, you can overdraw your account.
I work at a credit union, and we've heard horror stories from our members who have had multiple overdrafts because of this type of merchant policy. They come back from vacation with hundreds of dollars in overdraft fees, and no idea that was happening!
OP, if you don't want to get added as a joint user on your husband's credit card (after all, it's none of our business why you can't/won't do this!), perhaps you could use travelers checks or a prepaid Visa card for your trip.
But I do agree with another poster who suggested that you establish credit in your own name. It's a financially smart thing to do for every adult. My husband died in a scuba accident when I was 30, and I was so lucky that we were joint on our accounts. Who would have thought I would be widowed at 30? What was already an awful situation would have been much more complicated if I didn't have credit of my own, or access to "our" money on a joint account.