What's Up with Familarity

We enjoy being with someone familiar. The familiar face, familiar distance, familiar sense, things that can be understood without overtly being expressed. We treasure this kind of familiarity, since not anyone can be this close to us, so does this means this kind of familarity would make you tolerate to any kind of mistakes or disagreements?

I happened to experience this kind of dilemma.

She is someone that I'm familiar of, we've known each other for more than 10 years. Familiar? Of course. Since a long time ago I have tolerated mistakes after mistakes that she had made, and I think she had done the same thing to me, because both of us were young and naive, where I can think back of those silly times and laugh out loud. Those days were young, meaning we can be quite unwise to our decisions. But now I consider myself a grown-up, and she is definitely more adult than I am, why is she still making the same old mistakes over and over again?

I'm not saying myself is much better than her, it's just that I can see through those same mistakes that I've made, and why can't she?

It's a boy problem, I would say. I believe most girls have done the same common mistakes before, being too in love and starting to drown yourself in it. Where people around you telling you that it's not the right person for you, and you refuse to listen or understand, and when you really get the consequences, you'll regret. I myself was in this kind of situation before, and I woke up, after so many painful scars that I've gained.

With this pain I try to talk her out of this mistake, to avoid her getting hurt. But it was useless, she won't listen.

I guessed I've gone overboard. Obviously I've bugged her nerve out. This familarity was broken, she was distant, and no longer share her thoughts with me like she used to be.

I was heart-broken. She is one of those closest to me, and I don't want to lose it. But at the same time I don't want her to repeat those mistakes, so I doubted my own choice. Am I doing the right thing to stop her? Yes she is an adult now but I was reminding her, am I in her way?

For this familiarity between us, should I tolerate with this? Should I just let go?