If you were to travel alone, you're going to unfamilar territory. The reason why I believe travelling alone is fun, also a bonus if you're single as well (You don't want to be in a relationship and your spouse nags you in the middle of the night due to time zone differences, lol) - it pushes yourself. It challenges how you see yourself, as you're surrounded by people who don't know - hence, you're free to be the introvert or extrovert you're not at home.

I have travelled alone in the past, I felt comfort when I do it because I'm used to it and always up for any new challenges in life. Plus, I don't need to pay for 2 people during lunch, so that's a good thing and I can also have a 5 star hotel all to myself. Downside, you need someone to take photos of you or you're alone with your camera's timer and that shit is hard to get a perfect shot.