My brother died when he was 42, not long after we lost my dad (67), my Brother in law (44) and Mother in law (70). Many more lost since that couple of years.
It's hard but I've accepted that there was nothing I could do and they are gone.
A short while after this my work engaged a program called "my best year yet" where basically you looked at a few things that you wanted to improve in your life and pared up with a colleague and came up with a list of goals to either achieve or improve the things you wanted to.
It sounds really cheesy, but it did make me take proper stock of things and I did improve my life. We actually ended up switching partners quick quickly when we realised that there were better matches. One of my things was that we were struggling to conceive and I was not great with Doctors etc. This made me actually go to the GP and get help. Other smaller things too. Other bloke wanted to improve his relationship with his daughter, another thing was wanting to learn to cook so lots of different things.
I guess what it did was make you focus on things that were important and also things that you are able to change.
So in your case @ssd, maybe listing a few of those things and steps you could take to change them would help you feel more positive?
I.e. you hate your job and feel undervalued - you could think about what transferrable skills you have and start applying for something else. One thing I learned was that women tend to only apply for jobs they are already qualified to do, whereas men will apply for jobs where they meet some of the criteria and this is generally a successful.
Or you are worried about your health and that of your family. You can't predict or protect from eeverything but you can take steps to keep yourself fit and have a decent diet. Money, maybe looking for jobs will help with this or you could think about other ways to earn.
I dunno, don't want to make it sound simple as it isn't and I know how it is to feel in a big hole. I guess what I am saying is that thinking about and doing very small achievable steps can make you feel better in themselves as you feel you are taking some level of charge over things that you can. It can make all the things that you have no control over recede a little. Write it down, tick it off. Always good to put down a couple of things you've already done as it's good to be able to put some ticks down straight away :o