expression, godan verb (-ru)
be bothered; feel troubled; weigh on one's mind
Describes a situation or thing that becomes a source of worry or mental burden. Often used in the pattern 〜が苦になる.
彼の一言がずっと苦になっている。
That one remark of his has been weighing on my mind ever since.
人前で話すの
Speaking in public bothers me.