We all have that one friend who has been by our side for 10 years or more. At this point, you're basically sisters and she knows everything about you. What would we do if we did not have them in our lives? It just wouldn't be the same.

1. She has been there for you through everything.

Let’s face it, before college when you actually turned out to be a normal, decent-looking human being, she was there for you through your awkward stage. The braces, acne, bad outfits and highlights—she’s seen it all, and still loves you anyway. And on some of the more serious bad choices in your life, she was always there to tell you that you were wrong, and still there to support you after you did it anyway.

2. She knows you better than anyone

.When something is wrong, she is the first person you go to. She knows your temper and thought process, understands your moods and helps you evaluate why you feel the way you do. When you tell her about fights you get into with other people, she will say things like “I understand why you’re mad, BUT—“and explain things in a way that only you could comprehend. She knows all your favorite colors, movies, and foods, and even who you don’t like and why you don’t like them.

3. She is a part of your family.

Your parents and siblings have known her for so many years that she is basically your second sister. She walks into your house without knocking and has a favorite meal of your mom’s. You don’t even have to ask if she can sleepover and sometimes you feel like your parents love her more than you.

4. You know each other’s quirks and weird habits.

Since she knows everything about you, she totally accepts all the weird parts of your personality, and so do you. You just get each other and each of your strange qualities, because they actually complement each other…

5. She tells you like it is.

Because you’ve been friends for so long, you know exactly what makes each other the angriest. And when that point comes, there is no beating around the bush. You both tell each other exactly how you feel and why you’re mad, and then you are both over it in 10 minutes. True friends can’t really stay mad at each other.

6. Your significant others have to get the seal of approval from her.

If you start dating someone, you have to make sure she likes them. She knows you better than anyone and always has your best interest at heart, so if she has a bad feeling about your boyfriend or doesn’t think that you two will fit together, that relationship will definitely not be working out any time soon.

7. She is the best supporter.

Through all of the good times, she is there to cheer you on and be your biggest fan. She is always the most excited for you when you are succeeding, and always your shoulder to cry on when you’re not. Who else knows exactly how to cheer you up?

8. She does not judge.

No matter what bad decisions you make or if you constantly ask her the dumbest questions, she never judges you and is always there for a second opinion on any important (or non-important) life matter.

9. You are each other’s life partners (in a non-traditional sense).

A lot can happen in 10 years, and for someone to stick by your side through it all is extremely valuable. You know that she will be there for your wedding, babies and beyond that. You will be each other’s children’s Godmothers and always be there for each other at life’s most important events.

10. You don’t know what you would do without her.

Life just wouldn’t be the same without her in your life. She is you non-biological soul sister who helps you through everything. Thank you for all of the late-night food runs, crying phone calls and the uncontrollable laughs. Thank you for being a constant in my every day life, and thank you for always sticking by my side. I don’t know what I would do if I didn’t have you.