あなたがそんなに気分が悪いなんて気づかなかった。

I wasn't aware that you were so ill.

あなたがそんなに気分(きぶん)が悪(わる)いなんて気(き)づかなかった。

Anata ga sonnani kibun ga warui nante kizukanakatta.

貴方 (あなた)

you (referring to someone of equal or lower status); dear (what a wife calls a husband)

が (が)

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

そんなに (そんなに)

so much; so; like that

気分 (きぶん)

feeling; mood

悪い (わるい)

bad; poor; inferior; evil; sinful; unprofitable; unbeneficial; at fault; to blame; in the wrong; sorry

なんて (なんて)

such as; (things) like; exclamation

気付く (きづく)

to notice; to recognize; to recognise; to become aware of; to perceive; to realize; to realise

Readings: キ、ケ、いき

Meanings: spirit, mind, air, atmosphere, mood

Readings: ブン、フン、ブ、わ.ける、わ.け、わ.かれる、わ.かる、わ.かつ

Meanings: part, minute of time, segment, share, degree, one's lot, duty, understand, know, rate, 1%, chances, shaku/100

Readings: アク、オ、わる.い、わる-、あ.し、にく.い、 -にく.い、ああ、いずくに、いずくんぞ、にく.む

Meanings: bad, vice, rascal, false, evil, wrong