How much older would that be utamea? I am almost 70 years old, but I am also a Pagan, and I follow a Traditional Witch pathway.
I am not a Satanist (or along those lines 🙄), and neither are the very many other Witches that I either know, or know of, and many of them are of a similar age to me - although there are actually adult Witches throughout the age spectrum in the UK.
Also, please don't think that we are peculiar to the UK, I know for a fact that both the USA, and Australia, have a very strong presence of Witches as well, although many of them follow the Wiccan Pathway. There are probably Withes in most democratic Countries, but I do realise that unfortunately in some places their Witches do tend to folliw a somewhat darker, or sinister - left-hand - pathway, but thankfully most of us will never cross paths with them, as I understand that the majority of them tend to live in more exotic, or specified places.
British Witches are mainly kind, and compassionate people, who love and care for all of nature, animals, people - particularly children and more vulnerable adults - but the vast majority of us do not think in terms of 'white Witches' or 'dark Withes' (neither of which refers to the colour of one's skin), on occassions we do need to perform spells that some might call curses, but they can be very dangerous spells to ourselves, if we don't prepare and cast them with great care. But we are usually much more involved in protecting the things we hold most dear,
although the majority of us probably do not suffer fools gladly/wisely/happily!
I'm sorry utamea, you are probably thinking WTAF is this - old - woman going on about, as you only made a casual, almost throw away, comment?
Unfortunately, I am really fed-up that so many Mumsnetters appear to think, like you seem to think, that if we are older than - what? 45? 50? 60? - that we are out of touch, and have no idea what makes the younger generations tick. Anyone of roughly my age, have already been a teenager/young adult/middle aged, and we have had nearly all of the same problems and issues, that you 'youngsters' have had - except, of course, yours have been magnified almost out of proportion, by the introduction of smart phones and social media. However, many of us have adult children now, who we have seen struggling and suffering - and yes, I mean suffering (I am so grateful that I grew up before the age of the Internet took off) - from all of the bullying, and influencing, and videoing, and being available to both friends and foe, all day, and even all night for some. So even though we might not be very knowledgeable about all of the up-to-date terminologies, or the meaning of an emoji when it apparently doesn't mean what it looks like it should mean, many of us, with even an atom of common sense, can relate very well with your emotions, as we have already been there before.
So, to return to @Orchid90's problem, her MiL is just a rude, and unfriendly cheeky fucker, and has probably been like that for most of her adult life. OP, if you have been stoic enough to read this far, I would have been tempted to do what a PP suggested, and put all of the decorations back up where you had them, although you were probably too tired out by that time to be bothered! Your MiL needs to be told very clearly, by you and your DH together, that if she ever does anything like that again, that will be the last time that she will be invited in to your home.
If, as utamea believes, your MiL has any ridiculous ideas that putting up some fun Halloween decorations is at all wrong - for whatever reason - maybe you could point out to her that the awful and scary place that the Earth has become, is not due to any occult goings on, but rather to the negativity and evilness that any individual human being has inflicted on another.