I have struggled to find graphic novels for adults as well that are not geared towards boys. This is partially why I joined this forum for I have found most in book stores I visit when I travel. I highly recommend Crawl Space by Jessie Jacobs it is my all-time favorite non superhero/indie/alternative graphic novel.
Crawl Space is about a teenage girl who finds a portal to another dimension in her washing machine. The story is light hearted with some head scratching sci fi elements. Not to mention it is visually breathtaking, the cover speaks for itself.