I've offended my in-laws

@Ad Lib

Lots of advice, most of it very practical, as bad feelings aren't good for anything much. But it seems to a complete outsider that you have not been distracted, you have been very focused on what matters most to you (it's no sin that this is not your in-laws for the moment). I found most people actually did understand that cancer was a big impact, even if they were short on details. I suspect your in-laws may want to be a part of it all, to be supportive, with good intentions, but not maybe the best sort of application. I tend to agree with sophollie, that a little tactful intervention from your husband with his parents might be timely.  But preferably on the lines that you have a lot to deal with at the moment and will chat with them in due course rather than hinting at any emotional turmoil. Cancer is hard enough, any assumption that your marbles go out the window too should be snuffed early!! Strength to you.