I guess you just have to weigh the benefits that getting into this relationship would bring against how set in your ways as a single person you are.
If the companionship/emotional support/intimacy is something you would welcome, and you're willing to sacrifice some of your solitude for that, then it's potentially worth pursuing. I'm almost 30 and got married two months ago, and it IS a change having someone in your life pervasively after years of going solo, and as an introvert, it takes some fairly big adjustments. In my case, my wife is someone I knew for a long time and had a track record of meshing well with, so it really does matter the type of person this girl is too. If she's a dramatic, easily driven to confrontation kind of person, that might drive a person whose used to peace and quiet a bit crazy. Or if she's an affectionate, emotionally demanding person, that might take some adjusting time for an independent individual.
Based on your description of her as someone who "gets you in a way most don't", then it sound like she may be the kind of woman you can work and develop a relationship with that's fulfilling for both of you. Provided the likely upheaval in your set way of life is worth it to you, the signals seem to be there that she's waiting for you to reciprocate interest.