I was not there last week at all, but I was planning to be there tomorrow.
I think it would be fine to skip a week if it will be so few of us and if you would like to get some good solid sleep.
That is so important, and I also appreciate that you get up each week in the middle of the night for us.
But it is OK to think of yourself and take this time to rest, especially if you are still feeling sick at all.
Honestly, I could be selfish too, because I started my treatments again yesterday, and I expect to feel pretty lousy tomorrow - it always hits me the worst on the second day (which used to be Saturdays).
If you want to chat for a little while when you get up on Monday morning instead, send me a PM or email and I'll log into chat. I am usually up until about 1 am because I sleep some in the afternoon or early evening.
I'm sorry if this is so vague and seems to be throwing the decision back on you, but I support your decision 100%.
If you understand everything, some things are just as they are. If you understand nothing, things are still just as they are.