Is it normal that i want to propose to my best friend?

Hi. I'm a 20-yr-old White woman and I have this best friend named Katrina (she's Black) and well, I think I've fallen for her. I've known her eversince Kindergarten. The only problem is, I left my homestate and I haven't seen her in 2 (almost 3 years). Last night, I dreamt that we had gotten married and it made me realize that I love Katrina more than I know and I want to be with her for the rest of my life and maybe even have a family with her (through Artificial Insemination, IVF, or Adoption). Now that I think about it, I think I always had something for her even back when we went to school together. There were times where I held her hand and even kissed her a couple of times (once on the cheek, once on the neck). I was thinking if I ever moved back and saw her, I'd take her out for food or something (It'd secretly be a date) and I'd propose to her (Or, it'd be a series of outings and trips then I'd propose to her). But then again, even if I did see her again, she'd probably be married and a mother by that point. If that's the case I'll still confess to her but I'll try being there for her as a friend (I might even become her childrens' Godmother). If she's not married/doesn't have a boyfriend though, I don't think she rolls that way but I'd still do anything in my power to win her love, you know? If it still fails well, atleast I have a Unrequited Love going on. If she were bi or lesbian though, what makes me think she'd sleep with me and make me her significant other? Another problem is that if I can't have her, then I don't want anyone else since I feel as if my heart only belongs to her romantically and sexually. I just hope that even after I confess my love to her and ask her to marry me (If I get the chance to), it won't ruin our friendship and we'd still be able to be friends even if she rejects me. I'm sorry if my post is long.