I am very confused. I've been in relationships, but I've never felt an emotion stronger than just a simple crush, relationship-wise. I've never felt an urge to kiss or anything beyond that with anybody. I'm so scared, I really want to be able to grow up, find the love of my life, get married, and have children..but everything in my life says that's not possible. I guess all I want to know is if I am capable of loving somebody like that?
The first thing to do is give yourself a break. You are a lovely person just as you are, at this moment, with a wonderful journey ahead of you.
I think you are capable of deep love and intimacy, but whether you will choose it or not is another question. For some people, such relationships are just not part of their life path, and that is OK. It's also true that unless you are happy with yourself, you are unlikely to be happy with anyone else. Those are two good reasons for building a strong single life, whether you remain single or marry.
I'm sensing a strong monastic energy around you. It could be an unresolved soul conflict from before you were born; in a previous life you may have been a nun, monk, or priest who struggled with the vow of celibacy, for example, or a young girl who wanted to be a nun but was forced into marriage. Regardless — in the here and now, what I see is that you really want to do things right. You see others in relationships, wonder why it hasn't happened for you, and think there is something wrong with you. And I really don't think there is.
You, your life, and your range of emotions are all unfolding. You are capable of more than you imagine. All will be well if you allow it to be.