The Girl From The Sea by Molly Knox Ostertag (author and illustrator)

From the author of The Witch Boy trilogy comes a graphic novel about family, romance, and first love.
Fifteen-year-old Morgan has a secret: She can’t wait to escape the perfect little island where she lives. She’s desperate to finish high school and escape her sad divorced mother, her volatile little brother, and worst of all, her great group of friends…who don’t understand Morgan at all. Because really, Morgan’s biggest secret is that she has a lot of secrets, including the one about wanting to kiss another girl. Then one night, Morgan is saved from drowning by a mysterious girl named Keltie. The two become friends and suddenly life on the island doesn’t seem so stifling anymore. But Keltie has some secrets of her own. And as the girls start to fall in love, everything they’re each trying to hide will find its way to the surface…whether Morgan is ready or not.