Why did carlise Cullen bit Esme Cullen?

it was similar to edward's situation.....she was on the brink of death and so he saved her because Esme was his 'Tua Cantante' (just like Bella was for Edward). According to SM Carlisle and Esme met when she was 16 (he treated her for a broken leg.) She never got over the experience of meeting him and neither did he because as soon as he recognized her in the morgue (after her attempt of suicide) he decided he couldn't let her go again. You know how once a vampire finds love; has found his soulmate...Esme was Carlisle's soulmate and he found her after almost 200 years alone. ♥ That's why he bit her.