Anime hog?

My best friend is currently watching a anime that I have stalled. She seems to have connected with the characters already and is sending me snap chats about them. The thing is I watched this anime when I was going through a really tough time. I feel like all the anime that I've wanted to watch she already has and now she's watching this one. I usually am happy to see her watching an anime I have already watched so we can chat about it, but I haven't finished this one and if she does before me I don't think I'll be able to handle it. I don't know why I am so worked up about this but I feel like nothing I do will ever be mine. Like at my house nothing I have is mine and I'm constantly reminded of that. For once I wanted to have something that she didn't already have. An anime she hasn't watched yet... I know I'm being a brat and totally selfish! But I can't stop thinking about her finishing it and leaving me behind. I still have time to finish it but I really don't want to watch it right now... but if I don't she'll end up finishing it and crying to me about how amazing it was. I know some many other anime watchers have already seen it and are huge fans of it but it's different for me when she's my best friend. I feel like I am constantly being one-upped by her; she's smarter, prettier, more skilled, in better shape, better with guys (she doesn't even care about relationships!) Why can't I have one anime, one thing that I've finished before her. Sometimes I wonder why I  act so childish when it comes to her.. I'm not worthy of her friendship. Jealousy isn't what makes you friends, but why can't I stop acting this way? I really hope that one day I can be a adult and act maturely about things like this. If only I wasn't so angry maybe I could resolve this.. I'm sorry.