My first advice would be to take any ideas and feelings of 'awkward', ball them up into a basketball, and slam dunk them into the trash. (How's that for awkward?
) I see too many people let life and people pass them by over fear of awkwardness.
A person with whom you don't get deeper into things with may not be ideal for a mate for you, but why not friend material? Not everyone you're going to meet will be on that level, but it doesn't mean they don't have the potential to be entertaining company. And compatibility for friendship can be different than compatibility for a romantic relationship.
To open the relationship back up, you'll have to contact her. Be clear about what you want. These are my words, of course, but perhaps something like "Hey, I'm sorry about abruptly ending contact with you. I've been thinking over the last few days, and while we may not be couple's material, I really did enjoy talking with you and hanging out with you as a friend, and I've been missing our interaction. Would you be open to a friendship relationship?"
Yeah, it'll be awkward, but good friends are hard to find and worth the risk.