A brilliant performance by the main character. Julianne Moore coped with the role a hundred percent, I have not read the book by which the movie was made, but I am sure that the author's idea, it looked like that.
Gestures, facial expressions, speech, situations, reactions... A man losing his memory. Day in and day out. One day you are an educated, respected person in society, and tomorrow you are reminded that the person you are now interacting with is your own daughter. And the way the people around you - your own kind, your loved ones - have to live with that. And while the disease hasn't yet begun to progress, you're trying to do at least something to make it easier for everyone.
This film will be understood and felt first and foremost by those people who begin to lose any possibility to exist/live a full life because of some disease. Those who are losing their sight, hearing, etc... Gradually, not immediately. People who know that they will become 'handicapped'. Or those who had it happen to their loved ones...
Alec Baldwin's performance was amazing, amazing, I believed him completely and unconditionally from the first minute... as there are no complaints about my 'not my favorite' Kristen Stewart. She grew in my eyes as an actress here, unequivocally. The other characters are minor, but played no worse, for example, dearly worth the reaction of the heroine's son/daughter during her speech at the clinic.
I recommend to watch this movie because such dramas teach us to accept the inevitable when it becomes clear that sooner or later all the things we don't want to happen will happen anyway. There's no need to despair, no need to play the victim (to both sides), no need for any of that at all. You just have to live. If possible - decently, as much as possible - tolerantly, according to conscience, in general. And, as the mother of the main character correctly said, try to live life vividly. Just live.