@PamelaDoov, what if I told you there was no way to get from today to, for example, this summer, without letting somebody down? You are human, you have limits! This might sound harsh, but you will eventually run out of energy. So you need to prioritise who gets your energy and who can cope without.
Can I guess that you would rather let your work colleagues down than your son or partner. You would like to be healthy and rested rather than completely burning out.
I'm really sorry to be blunt, but you'll get through this in better shape if you accept that you're going through an incredibly painful, difficult experience and you need to make accommodations. Think of it this way: if a colleague needed time off because they were grieving AND had just had surgery, I'm sure you would understand. That's you - you need to trust that others will treat you with the kindness that you would treat them.
Sorry, this is a very brutal post, it's hard to convey tone! But please, email work and say you need more time. Tell them you have food poisoning, tell them you've fallen down a well. You aren't letting them down, the team, company etc will continue on just fine for a few more days without you. I promise.