I spent a lot of time being confused by this, listening to perfectly healthy young people with good paying jobs and no attachments telling me "I wish I could just drop everything and go traveling for months on end like you do" and then just sort of trailing off. "But You Can!!!" I always wanted to shout back. You just don't actually want to do that. Or you would. What that person really wanted was what they had: a stable comfortable job and a nice car and apartment, practicing for the day when they had a wife, kids, lease & mortgage to solidify that reality of "can't go traveling". Sounds pretty comfy, actually. If only they could come to grips with what they wanted and be happy with it.
It might be worth stepping back and looking at what you actually want. You just might find it's what you already have.