Jealousy is something that (I daresay) everyone suffers in. You always want to be like someone else. Might it be your looks, occupation, brains, riches...blog. There's always someone who's doing better than you and who you want to be.
There are so many bloggers that I wanted to be for their originality and likeability-ness. So many of them that have thousands of followers and tens of comments. Because of this, I started hating myself and going "why can't I be like them". That blogger got all the love, all the ARCs and all the opportunities while I was just...there.
It got so bad that I ended up secretly hating one for absolutely no reason. In my mind, though, I didn't really think of it as hate. It was more like a passionate envy and I couldn't stop comparing myself to said blogger. And because of that, I had ill feelings towards them. I'm still having a little trouble with that, but it's gotten better; minus the ill feelings. (We're actually good friends, now!)
The moral of me saying this is that everyone suffers with jealousy. And it can go to the point where it really starts messing with your mind. I may never be free of wishing I could be someone, but that "someone" might change. There is always someone better than you (in a sense) and someone you're better than. What I learned is that I need to keep it in the dark and surround myself with things that make me feel special. Things like all the blogging friends I have and all the ARCs and I actually have as opposed to what I don't have.
And trust me, it's going to be hard. If you're feeling at all like what I am or have, you get it. I'm a naturally jealous person even though this isn't a competition.
Remind yourself why you're blogging. Because for me, it isn't to be "popular"; it's to spread my love of books. And maybe if I keep telling myself that, I'll believe it.