i don't need to try on every dress to know that it's the right one

I titled this blog with a quote that Tina said to me today.
I was telling her how i wanted to see what's available out there for me, how i wanted to maybe date other guys to see how i feel. I don't want to feel "trapped" but when she mentioned this quote, i felt as if it was true. I feel inspired (just a little).

When i went prom dress shopping, i tried on a total of 3 dresses.. and i fell in love with one. Right at that moment i knew it was the one, but yet i was questioning whether or not i should try on a couple more dresses. In the end, i bought the dress because i didn't want to try on anymore plus i didn't want to risk my chance of losing this dress. But now, whenever i put on the dress, i don't feel as in love with it as i was.. If i was given the opportunity to buy another dress, i would.

This is what i don't want to happen with my boyfriend. I love him with all my heart, but there are just things that make me question and doubt our relationship. These factors have caused me to want to maybe try other guys and see.. but yet at the same time i don't want to do something that i might regret or lose the one that i should really be with. He's a great guy, but i just don't want to feel as if i'm tied down. I don't want to be in this relationship for the sake of being in a relationship. In a couple years, i don't want to have the feeling of "if i could, i would".

Can't someone understand?