absent I am sorry to hear about your loss.
Strangely I don't see myself as a believer in Angels, a God or an afterlife, which sounds a bit vague I know. Perhaps unconciously I am hedging my bets!
My parents died 10 years ago within 2 months of each other. Dad first at 86 and then Mum at 82.
Some time after their deaths I dreamt that a sort of angel figure complete with white gown, came floating down from heaven, hand in hand with my mum.I asked my Mum if she had met up with my Dad yet! I cant remember getting a reply. In the dream I somehow knew that "the white angel" figure was my Mum's baby sister who died when my Mum was about 2yrs old.
This was the oddest experience I have had. Like most of my generation I have been steeped in heaven and angel imagery, but I have never had an experience or dream like that before or since!
When your MIL has her funeral, write down all the good memories and funny anecdotes you remember about her. If you can manage it read it yourself, or get whoever takes the service to do so.
It really helps to bring back good memories and funny anecdotes to relatives and old friends, and in particular to let people, who only knew that person in declining physical and mental health, just what they were like when they were fit and well. They can then remember, talk and laugh together about the happy times.
I wish now I had done this for my MIL whose funeral seemed rather flat.