I can only echo the others, that your family is in for a shock. I've done the AC x 3 weekly chemo and I'm now on weekly Paclitaxol. Neither of them are a walk in the park. With the AC, I would be almost completely bedridden until Day 3, then I could get up and move around, but energy levels didn't come back until about Day 6 or 7 and then only allowed me to do bits and pieces. Through most of it, I have cooked evening meals but pretty basic, and we have had takeaway and the kids have also kicked in. I should also say that my 3 kids, now aged 12, 13 & 16, do all of the major housework each week on a roster basis (vacuuming, bathrooms, hard floors) and the older two iron their own uniforms. This was going on before bc and it's been a major lifesaver since.
You may be one of the lucky ones who cope with chemo really well but the reality is for most of us that we don't - we're lucky if we fall into the middle ground. It's not like surgery where there is a defined and easily observable issue. It's not something that you can just push through, so don't try to - while a bit of exercise is good for you, cooking and cleaning don't count.
I do get the bulk of the groceries online so that, hopefully, the staples and the bulky stuff is delivered. I always order that before chemo day as, particularly in the early part of the cycle with AC, there was no way that I could even sit at a computer for that long let alone think of what we needed. When the order arrives, the kids check it off and put it away.
None of this is hard for them to do although it may eat in to their R&R time - life's tough. BTW: the housework takes them less than an hour each a week - I don't expect wonders, although I do pick them up on stuff if it's obvious that they've just been slack.
They've all got simple recipes that they like to eat and can do easily, so that helps.
Of course, none of our advice will help if you've not got people on your side at home about this. That can make things so hard. Has your husband been in to see the onc with you? Maybe someone else telling him will help. And your kids and the fiancee should be able to see the need to pull their weight. I'm guessing that the older two pay board. If so, what is it calculated to cover? If it's meals and cleaning as well as room and bills, then maybe it has to be adjusted - if not, maybe it still has to be adjusted and get a cleaner in. You don't say what your husband does so I haven't commented as for all I know he may work really long hours or 2 jobs, but if it's just mowing the lawns every couple of weeks then taking part in running the household should also apply to him. But I do understand that it can be hard to change the roles of a lifetime if you're meeting denial. Taking to your bed and effectively going on strike may be your only option. Take care and let us know how you're coping.