Joss Stone is going through a bit of a drought at the moment, and so is thinking about plan B:
"I think I'll have to turn lesbian. Every girl my age wants to be in a relationship. I haven't had one in two years and look how that ended."
Of course, it was just a passing remark, but it's not entirely helpful to pretend that lesbianism is a thing you choose to match your mood, which is similar to the line taken by those charlatans who claim they can "fix" gay people.
And even if you could "become" lesbian, Joss, why do you think that would make a difference? Could it be that your failed relationships are because of the way you approach them, rather than the gender of your crush?