Since kindergarten, we’ve been told that sharing is caring. That sentiment is nice and all when you’re young, but as you get older (and start dating) it’s not just about LEGOs and play-kitchen hot dogs. Nonetheless, based on what you’ve been taught, you think, why not lay it all out on the table bathroom sink? Here’s why not: Because if you start sharing every little thing, before you know it, you’ll morph into one person, which is to say you’ll basically be dating yourself. Weird! To prevent that from happening, may I suggest keeping the following things to yourself?

1. Toothbrush. Do I need to explain?

2. Netflix password. What happens if you break up? Then what?

3. For that matter, any password at all. Do you really want them seeing your seventh grade selfies you keep hidden on your computer?

4. Less than a queen-size bed. Bigger bed = less sweat and less duvet hogging. Or you can just sleep in separate beds like people in the ’50’s.

5. Razor. I did this once in a time of desperate need, and I still worry that I contracted something that I just don’t know about.

6. Any secret you wouldn’t want them knowing if whatever you two have going ended.

7. A washcloth. I don’t want your pimples infecting me.

8. A bag of chips. There aren’t enough in there to even make an acceptable snack for one.

9. Details of the best sex you’ve ever had (that wasn’t with them).

10. Where you put all of the boogers you pick sans tissues when you’re alone. Trust me, you do not want them finding your snot shrine.

11. A boss. Work relationships are awkward — have you seen Angela and Andy from “The Office?”

12. A picture of your poop that you swear looks like Bruce Willis.

13. How you really feel about their mom/dad/any other family member.

14.A sleeping mouth guard.

15. NUDES THAT YOU CAN’T DELETE! (aka not on Snap, and even then… it still probably exists in some cloud.)

16. Money. Unless you’re married, I guess? But like, what if they suck at personal finance? I’m planning to always keep a stack of casheesh hidden under my mattress.

17. Pizza. All pizzas are personal, OK?