I've found out. And it's pretty gross.

True love is a man who looks at your puke.

Food poisoning came back Saturday morning and BF wanted to make sure he didn't need to take me to the hospital. Because the Internet told him blood in puke meant a trip to the ER might be necessary, he took it upon himself while I was writhing and wailing in bed to go into the trash and look at my puke to make sure it was just puke. He didn't tell me until hours later, and I have never felt so loved.