I do realise it's not that easy, many get through the tough times and some do not.
Every single person suffering needs a different approach, but the best way to start is to try talking and not just saying cheer up. I often think people who see the world through a depressed state are seeing reality, the rest of us are over confident.
I may sound blunt to some, but if there is no conversation at some point there is little chance of a good ending of its heading south.
The sooner something starts the better, some will subtly ask for help but those around don't pick up there is a problem lurking. Talk to your loved ones and talk often.
There are often others affected. In my world people commit suicude by jumping in front of trains, this can affect several families, the one directly impacted and one each for the two drivers plus the ambulance workers. I have seen the results first hand and needing to wash ones boots after is traumatic.
Yes it's not easy, yes some won't talk but yes some might.
R U OK ?