Your best friend, your go-to, your day one. When you're a single girl, your best friend is the one you rely on for most boyfriend-like activities. You spend all your time together — almost to the point where it annoys other people. There's nothing you wouldn't do for each other. If one of you were a boy, chances are, you would already be married. Here are 18 signs your best friend is basically your boyfriend.

1. She's the first person you text when anything happens.

See a cutie on campus? Get a free T-shirt? She's the first person you tell about anything exciting that happens to you, and even if it's super menial, chances are she'll be just as excited about it as you are.

2. You consult her before making any life decisions.

There's not a chance in hell you're sending that text without her approval.

3. You're always on each others' side.

Whether you're battling with your mom or one of your friends, she has your back and listens to your venting. Even if you're being dramatic and it's over something stupid, she'll support you, and you do the same for her.

4. You bicker about dumb stuff.

Like an old married couple.

5. But you can never say mad at each other.

She might do something to piss you off, but it never lasts more than a day. Something hilarious is bound to happen that you absolutely have to tell her about.

6. You buy each other meals.

Or really just alternate who buys the pizza.

7. You get jealous when a boy takes up too much of her time.

You get just as excited as she does when she gets asked on a date, but watching "Bob's Burgers" on a Thursday night seems much less pathetic when you're in it together.

8. If you don't live with her already, you have plans to live with her.

Because there's nothing better than living with your best friend.

9. You keep each other in check.

You call each other out when necessary, and keep each other sane. When you go out together, you know she's not going to let you do anything too reckless (unless she's being reckless with you).

10. She knows you better than pretty much anyone else.

She knows exactly what Instagrams will make you laugh and which boys have made you cry.

11. She's always there to rescue you and give you rides.

You don't have to worry about being stranded, because she's always willing to help a sister out.

12. You have more pictures of her on your phone than anyone else.

Between all the Snapchats and photo ops, all your cutest pics are with her.

13. There are no secrets and no judgments.

No matter what you do or say, she won't judge you. She's much more likely to just laugh at you.

14. What's yours is hers.

Clothes, food, and especially that one necklace that simply goes with everything.

16. People automatically associate you with one another.

If someone can't find you, she's the first person they ask where you are. Your location is constantly shared with her too, so she'll definitely be able to tell them.

17. You know her iPhone password.

And you know she texted that one boy she's not supposed to.

18. You Snapchat and text all the time.

Even when you're sitting right next to each other. She never judges your ugly double chin potato snaps.