Yeah, I used to vacation alone all the time. I've been all over Europe by myself. If you want a relaxing vacation, why not go by yourself? Then you only have to worry about your wants and needs and you don't have to worry about making someone else happy. Plus if you do get lonely, people tend to be pretty friendly at places with a lot of tourists, like a resort or hostels, so you could probably find someone to have some drinks with if you wanted to.