Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:

You realize you're starting to yearn for someone way more than you used to. "Sh*t (した)... " you say to yourself. This wasn't supposed to happen. Anytime you start to adore someone like that you always know you're getting into a bunch of sh*t you don't want to deal with. Damn these emotions!