DH has been very seriously ill recently and is still in the early stages of recovery and I would reiterate what everyone else has said about looking after yourself and finding time to do things you like. I make sure I get outside most days, gradening and walking. I am keeping up my Tai Chi online.
There are other simple thingsyou could do: like finding time for long luxurious baths several times a week. Now, even the best restaurants do take aways, a really nice meal once a week, a daily walk, a weekly ambling shop. Find little things you enjoy that can be squeezed into your life and you must squeeze the time to do them.
You and your DH have had an awful diagnosis and both of you need to adjust to it, but looking at the Cancer Research site, it really is very helpful