The truth of being a writer on tumblr is that some of your work gets 2000 notes and other pieces you really like get 40 notes, and that's okay. It can be really demotivating but if it pushes you down to the point where you're thinking of stopping, people are going to miss your work. The people who do follow and appreciate every piece you write will be missing out. The next piece that you could have written could get more notes than anything other you've ever written.
So don't stop. Don't stop writing if it's just because one piece of work didn't do as well as you thought it would. If you ever stop, stop on your own accords.
And if you want to start but don't know where? That's a different story. Take it one step at a time. Publish the work. Add tags onto it. Someone will read it and like it, that's a guarantee. In fact, if you want to post something for the first time but are scared to, ask me to read it! I would love to help. And if you need tips, you're at the right blog.
I mean we've all heard of girls' girls, but what about writers' writers.