I've been depressed recently because of (due to) this job.
「この仕事のせいで最近憂鬱だ。」は英語で「I've been depressed recently because of (due to) this job.」という意味があります。
仕事のせいーBecause of this job・Due to this job
最近ーRecently
憂鬱ーDepressed・Dejected・Blue
例文
「お年のせいだ。」It's due to your age.
「その失敗で彼は憂鬱になった。」The failure depressed him.