I got into writing because I like doing it. So why is it I get to do so little?

I’m now working on the second draft of my next novel, and it’s going a lot slower than I would like. This is mainly due to all the many other things I need to do. Marketing, in one form or another, takes up a lot of time. It just gets so frustrating sometimes. But if I don’t do it, people won’t know that my book even exists!