Too much masturbation is my usual diagnosis for people at a healthy age who are uninterested in getting laid. However, if your idea of what it takes to get some action is this:
"Building a relationship seems like too much effort. To get her to like me and for me to like her... I'd have to give up everything I do at the weekend for her. I don't want to do that."
...then I understand that you might be hesitant.