Lou, I come out of lurking to post a message in support.
I also have lost a DH to illness and I have said on other threads that, however you 'lose' your DH, you have to go through the grief process. Whether they walk out or die, the grief that the wife feels is exactly the same. It is grief for losing the future you had planned, grief because you feel a sudden loneliness. The person you would normally turn to when things are so bleak is the person who has 'gone'.
You describe the things I felt... the rock in your chest, the sheer enormity of facing the future, waking up every day after a fitful night's sleep and 'remembering' which means you have to newly grieve again. Time is NOT a great healer, but it allows you to learn new strategies to move on in your 'new normal'. It doesn't take weeks Lou, it takes months! For me it took 3 years.
The difference that widows have though is that we were never lied to, cheated on, disrespected or gas-lighted. We were loved to the last breath of our DH. Therefore, what you are going through emotionally is probably even harder in many ways.
I wish you strength, fortitude and dignity as you cope with your day-to-day issues. Just stake a step at a time and deal with what is important NOW. Put other things on the back-burner, but arm yourself with knowledge and information for when you need it.
You have the most incredible parents and friends - accept and cherish their support and wisdom as you forge your new life.
Lean on the MN peeps as much as you need. There is a huge resource of wisdom around. The decisions are yours - and yours alone - but this is a good source of advice when you need it..... or if ever you need to vent.
Love and prayers, SW