je suis fatigué

Quite straightforward, this one right? Fatigue is extreme tiredness in English, so this one's quite easy to guess. It can mean what it seems to say "I'm tired"

Most of the times I've heard this, it's rather been this thing French people say instead of

• I'm depressed

• I can't take this anymore

• I need good food

• I miss home

• I hate my boss

• My job's a dead end

• I'm not physically tired, just hurt

• I feel lonely

You can hence use this phrase when you're at a bad place.