We go thru the tripinsurancestoredotcom for our policy whenever we go on vacation. I first heard about them on cruisecriticdotcom, where they are highly recommended by frequent travelers/cruisers, and they are so easy to deal with. They work with you to find the best policy for your needs. You can go online for the policy, but I always call. We always have to get a policy which includes pre-existing condition; it isn't that expensive. It's peace of mind, considering the $$ invested in the trip. ( FWIW, a TA friend of ours had advised us to always get the policy independent from the cruiseline we were traveling on, or from WDW, as it has been her experience that it is often less hassle if you have to file a claim.)
We have several elderly family members who are not in the best health, and have recently experienced unexpected deaths of family members twice in as many years, so you just never know when you may have to cancel or cut short a vacation.