So recently I noticed I have feelings for my best friend but there's a few problems with this 1. We're both girls and my parents aren't okay with that. They think I'm straight but I'm pretty sure I'm bi, I just haven't told them or anyone else for that matter. 2. She has a girlfriend and I don't want to disrupt that. 3. I wouldn't want to hurt our friendship. She's one of the few friends I have and one of the even rarer that I trust completely. I really don't want to do anything that I'll regret or screw up in some way. I've been thinking about all this for a while now but I can't seem to figure anything out on my own. Please help.

Okay, here is a question. If you told her that you liked her would this affect your relationship as friends badly?
If so, I say give it some time and allow yourself to calm down. This will help you stay level-headed and not destroy what the two of you have built as friends.

So.. What i'm gonna say it's based on my experience and from what i've been through. i hope it helps.
I've ben livin all my life with this rule, to every "question" its either a yes or a no, no indecisions or anything like that. It actualy helped me narrowing down all my doubts and realized what i wanted and what is the best for me.
(This is from a straight point of view)
1- If you really think saying that to her will destroy all that there is betwen you to, and considering she is your best friend, you shouldn't tell her your fellings. But, i honestly dont think a true "best friend" relashionship can end just for that.. i mean those things are rare, its really close to family relashionship as well. And that brings me to number 2
2- If you think she can take it and it would be for the best to actualy letting her now, you should do it. If a true "BFF" thing ends just by that, i'm sorry but it probably wasn't such a true BFF after all.
But wait! There's a third option.
3- Considering you have fellings towards her i believe its safe to say that you want to date her. Hold that thought for me for a while and let me say this. relashionships 99% of the time don't last forever, wich means sooner or later the relashionship she's in will end. And that's when you enter. She will need a friend by her side, i mean im not saying for you to take advantage of her but if you are there for her when she needs and if you ain't in the "friendzone" she may grow feelings for you. Who knows if that already happend before and she was afraid of telling you cause she didnt knew you where bi?
All im saying is, don't think too much about it, just let it flow. If you end up liking someone else its ok, at least one problem is gone and now you will have a new one :)
If her relashionship ends and you still have feelings for her, go with it.. now that she doesn't have noone else it will be easy for you to take things a next step.
I know i kinda enumerated stuff but think about this and decide on what you should do cause you really need to know on how to make your one decisions. sometimes you will fail yes but you will also learn, and soon enough you wont be needing that much to rely on people and you will be relying on yourself. (not that there's anything wrong on relying on friends, etc)
I hope i helped you at least a little bit :)
Btw and i probably should have said that from the start.. im a guy xD

I know how you feel (though my experience is/was the other way around sorta), and it's one of the most frustrating things in the world. People always say love is patient, though, be it romantic or friendship-based. Don't try to rush or force anything, but don't force your feelings down forever, either. With the right shove, things tend to fall into place one way or another. All you have to do is figure out when that shove is needed!

Honestly, from what I know, these types of things hardly go over the way you want them to.

I'd say it's easy to make a decision now because she's in a relationship. That there is why you can't and shouldn't say anything. By telling someone in a relationship your feelings you don't even give them a chance to properly respond to your feelings or consider how they feel about you. It's like throwing water on the logs before even trying to start the fire. Best of luck; it all works out in the end.