When we dream, all the aspects of the dream...(people, places, events, emotions, colors, etc...) pertain to the dreamer, and their conscious, and subconscious selves.
So, from her standpoint:

Daughter - The daughter can represent what happens in the marriage, or 'union', of the parents. The child is what has arisen from the bonding, however momentary, of two people. In dreams, the child is sometimes used to depict how the relationship of parents is faring. (IE: a sick daughter might show the feelings in the relationship being 'ill'. A rebellious child may suggest the parent feels their relationship is conflicted).
For a mother to dream of her daughter - feelings of support or companionship, feelings of not being alone in the area of emotional bonds. Also, a comparison of oneself at that age...( one's own urges, difficulties, hurts that may still be operative). The mother might see the daughter's youth, opportunity, abed have feelings about that. In this way, the daughter may represent her sense of lost opportunity and youth, or even envy.

Granddaughter - suggests a comparison between your grandchild and your own child. (example:if this child is particularly obedient, it may suggest that you would like to see these attributes in your own daughter, if your daughter is not conforming to what you feel is best for her).

Dead person - Usually represents some area of your life that has 'died'. It can refer to the 'death' of feelings, such as hopelessness in connection with relationship and the loss of feelings about someone, the depression that follows big changes in life such as the loss of a loved one, loss of job, loss of a child-(poetically and physically), a sense your life in general is without the stimulus of motivation and satisfaction( as if you feel like your life is going nowhere ). Also, repressed anger that is killing positive expression.
The dead person may link several of these feelings together, as symbols often represent large areas of experience. As such, the dead person could represent part of yourself you want to leave behind, to 'die' out.
Because the dead person is your daughter's boyfriend, and your daughter is a younger version of you, it may suggest you feel she would suffer a disappointment...much like an experience you may have had yourself

Telling your daughter "It's time to let go" - suggests you feel that of yourself. It's time to let go of old feelings, or the things that make you unhappy, or your subconscious feels it's time to 'let go' of your daughter, and allow her to have her own experiences, and to make her own mistakes.

Ear - represents subtle information, rumors, and intuition. That it was removed suggests you feel that your advice is not 'listened to'.

Ashes - represent what remains in experience, perhaps as memory or wisdom after the event or person has gone, something that has once 'moved' you.. but the feelings have burnt themselves out.
Ashes of someone or something particular - represents something or someone that existed in your life and was a living part of it, but has now gone. Perhaps feelings have burnt out and left only a shadow or shape of what existed before.
That it was your daughters boyfriend suggests that you may have once 'liked' him, but you now feel as though he has given you some reason to dislike, or distrust, him. Possibly feel that he is taking your daughter 'away' from you.

Rubbed on your neck and chest :
Neck - the connection between body(feelings and sexuality), and head(thinking and conscious will).... a weak point. Often refers to attitudes as in idioms. The neck is also the point up to which we can be easily, or safely, immersed in water Beyond that point, there is danger. So it can depict what we can 'take' in life, and what is more than enough. Idioms: 'breaking your neck'...'stick your neck out'...'dead from the neck down/up'...'I've had it up to here'(holding your hand at neck level).
Chest - where your heart is...where you keep and hide emotions, feelings and pride. In a woman's dream the chest symbolizes the ability to 'give' of yourself, also good feelings about womanhood.

The ashes in these ares suggest a feeling of burnt out emotions, and and feelings of heartbreak.
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Usually I would ask rhetorical questions, but as you are posting someone else's dream,...you wouldn't know whether or not they 'apply'. And asking them of your Mother may may put her on the defensive.

I can ask you...
Did your boyfriend do something to offend your mom?
Has your mother given you advice you didn't follow, or don't want to follow?
Did you and your boyfriend have an argument that your Mom was privy to?
You are living with your parents, but are you currently wanting to find your own place?


Hope this gives something to go on. Best of luck!