I went on holiday on my own once and it was one of the best holidays I've ever had. It was totally last minute and right after I'd broken up with my ex, I had a week already booked off work and I didn't want to spend the week feeling sorry for myself and being miserable at home, so I found a last minute deal and went. Was one of the best decision I've ever made.
Whatever your circumstances or reasons for going though I'd recommend it to anyone (unless you really don't like the idea of being alone - although if it's a resort type holiday it's really easy to meet people to hang out with), but yeah it can be really freeing and liberating so go for it