Yeah, if you told your parents, they're going to feel like it's the end of the world... So, I personally wouldn't, unless you're completely sure you know how they would react.
My advice;
1.
Contact them, they won't shun you or anything like that, but try to help you/understand the context of your problems; ie. parents/religion etc.
2.
Ask these guys too, they can give you good advice.
3. Do activities that you feel will keep your mind of "lesbian thoughts".
You need to keep in mind that if you're still young, then these thoughts might just be temporary and eventually go away.
As for the religion side of it, as long as you don't act on these thoughts, there's no sin in it.
Prophet ( صلى الله عليه وآله وسلم) said: “God has forgiven my ummah for whatever crosses their mind so long as they do not speak of it or act upon it.” [Narrated by al-Bukhaari (2528) and Muslim (127)]
Al-Nawawi (رحيم الله) said:
Whatever crosses a person’s mind, so long as he does not dwell/act on it or continue to think of it, he is forgiven for it, according to scholarly consensus, because it does not happen voluntarily and he has no way of avoiding it. - [Al-Adhkaar (p. 345)]If you don't actually know anything about the religion, I wouldn't bother commenting on it. There are many homosexual Muslims, who don't necassarily break any rules or boundaries within the religious context.
And more importantly, due to some Christian beliefs, people make the false assumption that all homo's go to hell in Islam as well. This isn't true, just because you might have homosexual feelings or you may even do the deed, doesn't mean you enter hell. Even if you did enter hell (for sodomy), as long as you're a Muslim, you still eventually go to paradise.