To be silently resentful of my MIL's earnest craft work?

[Puffykins]

My MIL means well. She doesn't live close to us, so we very seldom see her (in fact, she has only met DS once) but she has very kindly made him a quilt for his cot. Which is lovely.
This Christmas (his first Christmas) we spent with my parents, as we spent last Christmas (mine and DHs first married Christmas) with PIL.
I meant to make DS a stocking this year - I've bought the felt and everything, but somehow in between looking after him and buying all the other Christmas presents and everything else I didn't quite get around to putting it together, and this year Father Christmas put DS's presents into one of my father's skiing socks -which is what we've always used as stockings at home. I recounted this to MIL in an email, in a chatty sort of fashion, but made it clear that I fully intend to make DSs stocking ready for next year.
However, by return of email, she tells me that she's knitting DS a stocking. She also tells me that she's making him an advent calendar with pockets for treats. And, underlying all of this, is the assumption that we will go to them next Christmas.
I'm irritated on so many levels, and don't know if I'm being unreasonable or not - I'm irritated that she's making the same thing that I'm already making (and I know that hers will be superior as it will be better and not just bits of felt ineptly stitched together but that's not the point); I'm irritated that she's making an advent calendar when I've been looking forward to opening the doors of the advent calender that I have chosen with my children since I was a teenager; finally I'm irritated that she's assuming that we're going to go to them when my husband and I would love to spend Christmas alone next year - and yet I know that she's banking on our going as emails are saying things like 'I'm already thinking of ways to make next Christmas really special for your DS'.
Equally, I know that we don't have to use the stocking or the advent calendar - but then I'd feel guilty at her expended effort - and I know that I should either get my husband to explain about next Christmas or else just suck it up and deal with it (MIL has three other children and obviously we'd go and see her another time and are in fact taking DS up to see her next month, and she is welcome to come and see us whenever she'd like to but never comes. Despite my having invited her several times.)
Am I being unreasonable? Should I keep my seething silent?

Fancy a MIL swap. In 20 years I have always done Christmas (rod for my own back I know) and within a year or two it was expected. The PILs (now MIL) have never once so much as bought the DC a christmas present, except the year they came when DS was 2 - on Christmas day - and said it was silly to buy beforehand when the sales would start within a day or two. Not saying there haven't been some big cheques over the years, but never once a little something, carefully chosen and wrapped to open on Christmas/birthday morning.

Welcome to Xmas with kids and in laws and parents. Like Mothers Day it isn't really about what you want it's about keeping the peace for everybody and being seen to do the "right" thing. What you want doesn't really come into it. Accept that fact and grin andr bear it. Book a spa day in the new year and sweat out your resentment there.
Xmas, kids, and inlaws/parents are a fine balancing act and we all need finely tuned diplomatic skills to navigate them.

I'm making my ds a stocking, my aunt has made him one and my mum has given him one and my old one from childhood. I shall use mine as "his" stocking, the others can be decorations.

You can still use traditional advent calenders, I don't personally like the treat style pocket ones but if she wants to fill it as well then let her if she doesn't and isnt there all the time she won't know if you don't use it.

The visiting issue I guess she assumed because you went to hers last year, plus she hasn't had one with the new grandchild. Not sure about how you solve this, I too would love a Christmas just us but the guilt of mum being on her own since dad died (and they both loved Christmas) and my brothers not in a position to accommodate her means I always cave in. It's even harder now with ds and another on the way