According to the internal clock of his companion, it was night. Because there's no time in the TARDIS.
The Doctor wandered through the passages of his craft, exploring every room and corridor. As a Time Lord, he only needed an hour or two of sleep.
He passed by a decorative basket of fruit. It wasn't wax; it was real fruit sealed in a temporal bubble.
The Time Lord picked up a banana, musing on how he always used to like them. He peeled it and took a bite.
Amy Pond was awoken by a loud sobbing noise. She got up and ran to find out what it was.
The Doctor sat on the floor crying. The banana lay at his feet, squashed and wet with the Doctor's tears.
"It's a disaster," sobbed the Time Lord. "I like bananas. I always have. But now I don't. Oh, BLAST this regeneration! I can't even like my true love anymore! What's happened to me?" he had to stop because he was crying too hard. He picked up the banana and cradled it for a moment, then remembered how he hated bananas and threw it on the ground again. The Doctor stood up. "IT'S NOT FAIR!" he screamed and ground the banana to mush beneath his foot.
Amy stood in her nightgown. She hadn't an idea about regeneration, but she remembered how the Doctor didn't know what he liked when she made food for him fourteen years ago. She dug around in the fruit basket 'til she found a pear. "Try this."
The Doctor made a face. "Pond, how many times have I told you I hate pears? Oh, right, just now. I hate pears. I despise them. I loathe them, even. Once I blew up a whole planet full of pears. The pear plantation-planet of the people of Planet Poudle, if I remember correctly. They were renown for their purple hats. I have one or two Poudle hats in my wardrobe. Where was I? Oh, pears. That pear in your hand is my worst enemy. Be reasonable, Pond."
"Have you always liked fish custard?" asked Amy.
The Doctor thought.
Amy handed him the pear. "My point exactly. Just try a bite, Alien Boy."
Said alien boy grimaced and held the pear like it was a diseased rat. "I won't like it." said he.
"You're being a child."
The Doctor frowned and bit into the pear. He chewed slowly.
Silence.
"I-I don't believe it…" said the Doctor, staring at the pear. "I actually…"
"Like it?"
"Like it? I love it!"
"I told ya. Now eat it and go to bed. You promised that we'd go to Arcadia tomorrow, remember?"
"Yeah, I remember. I'll take you there tomorrow. First I have to write an apology to the people of Poudle. Maybe I'll get you a hat. Goodnight, Pond."
Amy went back to her room.
The Doctor got out a notepad and wrote on it: "Pilot police box to Planet Poudle and purchase purple hat for Pond. Apologize for blowing up pear plantation planet of the people of planet Poudle. Eat pears."
He happily finished his pear and went to bed.
He may have lost an old friend, but he gained a new one. And all was well in the end.