He remembered it well. It was a feeling that he would never forget in all his eons. He wouldn't forget it because he wasn't going to make the same mistake twice- something he was afraid that he was doing right now. He wasn't sure he would make it through again.

Can someone without a heart die of a broken one, he wondered.

If Sherlock was going to describe John, 'fragile' would not be one of the words. One of the reasons that he was drawn to HIS John originally was because of his strength.

But he didn't argue with Fates. He kept his thoughts to himself, for once.

"I... I will try. But I can't be human. I'm not. I never was. I don't understand those feelings and emotions that these... mortals have."