The ILs are staying. This morning MIL came in to interfere help with breakfast and declared that FIL would not eat grilled bacon, it had to be fried. All my bacon was under the grill. I had to fish some out and fry it.
Next, cups of tea. MIL makes tea by putting a teabag in milk (ewwwww) and then adding hot water. I must admit that I never do this unless she is stood over me and she has never complained, so I doubt she can even tell the difference. But if she spots me, she tells me how to make her tea.
I was brought up to say thank you if someone gives you a present or something to eat or drink, and never complain about it. If you are out and paying for food and there is something wrong, then have a word yes.
I get buying something that your guests like and you don't have in, FIL likes white bread for example so I got some, but aibu to think that when someone offers you a bacon sandwich or cup of tea, that beyond "no sugar thanks" it is rude for you instruct them how to prepare it? Is is really that difficult to eat a grilled bacon sandwich rather than a fried one?
(They have never ever in my presence complained about a cup of tea when we have been out somewhere.)