Balancing health - mental and physical, with work demands and rest isn't ever easy if you've got any challenges going on. Sometimes there are no right answers. Resting can help, because exhaustion makes everything worse, but too much rest and your body will suffer from the lack of movement. Anxiety and depression can be eased with rest, but they can also be eased by feeling like you've achieved something.

There's no definitive answer here, and what works for one person on one day might not work for that person on another day.

I find that 'doing' often helps in the short term. What self esteem I have depends on getting things done, making things and feeling useful. If I don't feel useful, it's not long before this deepens the depression and/or increases the anxiety. However, it doesn't have to be a high set bar. Getting one useful thing done in a day is enough, I have decided, and I hold myself to that.

Trying to rest doesn't actually work if you're fretting about something you think needs doing. If that thing is important - as well it might be - not having the energy is a massive problem. The longer it takes to be able to solve an issue, the more terrifying and anxiety-creating it can become. This often isn't irrational and can trap people in vicious cycles of fear, illness, inability to act and increasing problems that feed the stress. Too often the assumption is that anxiety is a brain problem, but more usually it's about how we're interacting with the world. Fear can be a very rational response to out of control problems.

So you may end up self medicating to get through. Sugar and other stimulants can be used to push through exhaustion. Alcohol and other substances can be used to force rest. More and less legal options exist. Formal and informal medications exist. Sometimes, buying time in the short term to solve the big problems is worth it. Sometimes the big problems don't go away, and every day is like running through a burning building and then you end up doing it while also dealing with addiction, or self-care strategies that have become problems in themselves. 

It's easy to look at someone else's life and see the mess and dysfunction and blame them for getting into that much trouble. Without seeing the process, you can't see what was once a viable strategy that has now become part of the problem. So often, it's the things we do to survive what we thought was a short term crisis that trip us up for the longer term. It is so easily done. Bad choices often don't start out as bad choices, sometimes they were the best choices we could make at the time, but they too have consequences.