Very sensitive subject about reactions to death of dp/dh

[helcarmar]

This is a sensitive subject so I don't want to post this in aibu because I don't want a bunfight. Nor am I going to put this in bereavement out of sensitivity to others. A close friend has lost her dh of about 30 years. We are close but not to the point where I can (and in this case I most definitely would not) ask her really personal stuff. We're supportive of each other, but both are a bit reserved.
Anyway, since her dh has died (about 3 months ago) her mood has changed and she seems happier. It feels so taboo to say this, but it does seem that way to me. I keep thinking that she will 'break' down or something but it's not happening. I don't want her to break down, don't get me wrong, but isn't it inevitable somewhere along the way? Aren't we all supposed to be devastated?
We both help each other, but it's kind of understood that she keeps certain things to herself and I don't wish to ask her as it is none of my business.
But I am curious as to her reaction all the same. I'm not judging her for her reaction, I'm not saying that she should feel a certain way. I'm just thinking: 'It's not supposed to be like this'. But this is not same as passing judgement IYSWIM.
So, with the relative anonymity of the web, what is to made of this? Is it normal to sometimes feel relieved at death of spouse? He had cancer but of the type that was fast-growing. Few weeks from diagnosis to death.
As I say, please, no bunfighting over this; I just want opinions.

My mil lost her husband completely suddenly when he was 58. He had never been ill in his adult life and then just dropped dead.

They were an extremely close couple; they did everything together and had a very happy 35 year marriage.

However, since his death she has not only got on with her life, but taken it by the horns. She's really broadened her social horizons and taken up loads of hobbies. She's travelled all over the world and has about 6 holidays a year!

Of course she misses him and was utterly devastated at his death, but she has always been incredibly contained and dignified about it. Her composure at the funeral and afterwards made it much easier for the rest of the family to get through.

She has never cried on her kids' shoulders or made them worry about her being alone and lonely. I really admire her.