500 Days of Lindsey?

I think my Sagittarius nature is the source of this post. I am constantly craving freedom. A part of me is afraid to get too attached to anyone or any place. Any time I let myself be vulnerable, I get hurt. When it comes to things like relationships I kind of wish it was possible to spend immense amounts of time with someone and love them; but never actually be in a "relationship." Something about that word alone turns me off and freaks me out. It's like I just need some sort of "out" or exit door. Like an insurance policy for my heart. 

In my non-relationship you can do everything two people in a normal relationship would do, and remain totally committed to that one person. You simply wouldn't have that heavy word "relationship" looming overhead. I believe this would be especially beneficial when two people are young. You can care a great deal about someone but you just don't want to be strictly tied to them. Relationships these days seem like death sentences. People take them so seriously and there is often a lot of jealousy involved. Who wants or needs that at a young age? The last thing anyone needs is a ball and chain around their ankle. Is it crazy for me to want to be in a relationship less union with someone? It seems quite rational to me. At least when it comes to protecting my heart. But, is this too much like 500 Days of Summer? When at the end of the day, the person you're "not" dating feels like everything you had together was just a lie? Is someone always bound to get hurt in this situation?

So my question for you: Is it selfish of me to want someones attention and affection without giving them the satisfaction of an actual relationship?