It's difficult to describe her behaviour, because the individual examples sound so petty - you also have to be under the same roof for a while to get the full effects. She seems really nice if you are out for a meal or having a chat on the telephone, except she never wants to just go for a meal or to theatre or cinema - you have to do what she thinks is helpful or good for you. It took me years to realise this. And she never really listens to what you say, unless it's something she approves of she will interrupt, change the subject or just end the conversation abruptly. The worst thing is to be either a guest in her house or have her as a guest in your house, it's just pick pick pick pick away at every tiny thing you do. Even if you try to comply wholly with her ideas or demands you fall foul somehow, it's incredibly demoralising.
These sound like little more than undesirable personality traits though, and I excused them as such by reminding myself that she has a heart of gold. Crisis in the family - she takes time off work and comes to help where she will tirelessly cook, clean, shop, launder, run you baths, give you massages (she's qualified in various therapies). She is, to all appearances, outwardly selfless and extravagantly generous with her time and her money - paying for everything, giving gifts, giving money. It's almost impossible to refuse her, even if her help is not only unwanted but actually a huge added stress.
When I decided the emotional cost of all this was too great I very very carefully but firmly confronted her about her need to control every aspect of everything that happened and how damaging her constant criticism was she completely disintegrated. 'How can you be so intolerant, I do everything for you, why can't you accept me as I am,' etc. I felt such an utter heel but also a tiny bit cross, never visited her again and let the phone contact dwindle a bit. Was unable to entirely put her off visiting me though.
So, when she gravitated towards a long term and much cherished friend of mine about 18 months ago I could almost hear a bomb timer ticking. It's just ended beyond horribly, with nice friend actually fleeing and hitching a lift from a stranger to get away. I joked beforehand that she would need therapy after her visit with the controlling one but she actually is traumatised.