Arnt best frirends are like sisters to girls...so why alot of lesbian/bi girls fall crush on their best friend?

Yes, many girls do say that their best friend is like a sister. The operative word in there is "LIKE". It's not actually your real sister...so sometimes attractions arise when you're that close to someone.

There are a lot of things that go into answering this question. It's not as simple as "bff is *like* a sister, so you shouldn't crush on her". There are biological factors as well as social norms.

Biologically, best friends are not related (I suppose in some cases it's possible that they are, but generally speaking, they're not). There is a mechanism that our brains use to tell us not to be attracted to people we grew up with. It's generally believed that if you know, live with, and/or are raised with the person before the age of six, you won't be attracted to them. There are people who were separated at birth (due to adoption or other circumstances) who find themselves falling in love upon reunion, because they find that they have so much in common, and that drive to connect with those you're related to was taken from them at a vital time in their development. Now, in adulthood, their bodies are telling them they've lost all this time together, and they must make up that time, and get SUPER close. Not only do they not have that mechanism in place that tells them not to be attracted to each other (because they didn't know each other prior to the age of six), but they also have a tremendous biological connection, which most adoptees (and others raised by non-relatives) have never experienced. It's a double whammy, and can result in some intense feelings.

What does this have to do with best friends? Well, they didn't grow up together, so their brains aren't wired to keep them from falling in love. Often, best friends have a lot in common, and we humans are wired to love people who have similar traits. So, biologically, it makes a lot of sense that bff's would also end up in a romantic relationship, or at least having romantic feelings.

And, of course, with societal norms, there are no boundaries between friends. There are really no norms in our society that keep friends from falling in love with one another.

So, even though I might love my bff *like* a sister, she's simply NOT my sister. We didn't meet until we were 11, and my sexual orientation means that I'm attracted to women. There's nothing keeping me from loving my bff in a romantic way. I don't...but I could.

ETA: Simba, by the time a person is 8-11 years old, that part of our brains that tells us we shouldn't be attracted to people we're raised with is no longer working. By the time you're that age, there is nothing biologically to keep you from falling in love with a friend.

Intimacy of the emotional sort is important to intimacy of all other sorts. Silly question or provocation? I vote for the former based on the youthful phrasing of the asker.

Recommend paying more attention to your own crushes and not worrying about other people's unless you have a personal stake in the outcome...

They are saying best friends are LIKE sisters, doesn't mean they are sisters. They fall for their best friends, but not often their sisters...

it means they have the clossness of a sister. like someone you can tell anything to, or just be yourself around, someone you enjoy hanging out with. they get so use to them and develop crushes on them. if you had a hot friend, wouldnt you wana hang out with them alot, thus turning into best friends. but it stinks when your best friend is straight...and your not.

Hum... people don't chose for who they fall in love with. That's why most jerks have nice girls. -.-

Second, best friends are supposed to be awesome people, so I guess that's why people fall in love with their best friends.

Lack of self control

sometimes love is just a feeling. a feeling like you want to be around them all the time, like you want to wake up to there smiling face everyday. you cant help it, its just a feeling.

if they are incests then yes i think so.

im not sure xD