Maybe you could start with small things for use around the house in calming colours. This may seem silly but knitting a small dish cloth for washing the dishes was a nice escape for me when I had too many things on the needles and they were all too big and I just wanted to knit something small and easy. The quicker the project the more instant the gratification. Plus dish cloths are useful!
There are lots of different patterns you can try with them too without it being overwhelming. I have 2 right now I use for washing dishes and they are great.
But you could make yours into something more Spa like. A a mall face mask, and a hand cloth made of a nice soft cotton and when they are done treat yourself to a home spa day. Relax in a tub of bubbles with your knits and pamper yourself.
If you still want to knit something for your grandson, hats are usually nice and quick to do.
I hope things get better for you.