About his unforgivable words

I read it.
I see... you can't forgive him because he said such terrible things about his mom and you... I don't know the details of the situation, but I feel that I understand your feelings very well. I understand your feelings from the bottom of my heart.
I don't understand his thoughts or consciousness, but maybe he said such terrible things without thinking too much about it.
He probably wasn't aware of that.
Once again, why don't you tell him clearly that you've been hurt so much and that it's something that would discourage you and your mother, and clearly tell him that you feel unforgivable.
It may not be easy for them to understand, but let's explain clearly, ask him to reflect on it, and ask him to apologize.
After all, politeness is necessary even in close relationships, and respect, and compassion are important.
We're going to live together from now on. I sincerely pray that he will sincerely reflect and sincerely apologize to you, and that we can sincerely respect each other and live a compassionate and friendly life together. And I wholeheartedly support you and him. We wholeheartedly agree

That hurts, doesn't it? Words that hurt both you and your mother.
Growing old is the image of my precious parents who have raised me (you) in the midst of so many hardships, over and over their lives. Not even imagining such a background and summing it up with the word deterioration is very disappointing and sad, isn't it?

Maybe he wanted to say that parents and children are very similar. I think she's a wonderful mother, just like you. But if that's the case, the words he chose aren't appropriate, are they? I made a mistake in choosing the words... even if I didn't mean to do that, it even sounds like an insult to those who received it.
So, what do you say only to people who are nice, too! When I got angry and wanted to do it, I burst into tears.

I think it's better to properly tell him how you feel. The slight misalignment or sense of incongruity gradually expands as an indescribable feeling. It's hard when that changes to not being able to love you anymore.

This time is important manners for both of them when considering future family relationships, etc. Please, just be the two of you who can tell and share.

1. “Unforgivable” is the opposite of love and sincerity
The anger and sadness you feel comes from your deep love for your mother.
In Buddhism, anger is called “shinni (shinni),” but it is not a “bad heart.”
It is also an expression of “a heart that tries to protect what is important.”
The moment you feel like your mother was being disrespected,
My belief of “respecting my family” was trampled upon.
That reaction is neither wrong nor hypersensitive.

2. Face the “unconsciousness” of his words
Even if the words he uttered without offense,
What left a deep impression on your mind was that
That's because it was a moment when he lacked respect for “your loved ones.”
In Buddhism, there is a “proper language (shogo)”
Be humble in your words, even if they light a light in the other person's heart,
There is a teaching called that.
Looking at your tears, the fact that he “apologized without knowing what he said” also means that he still hasn't fully understood the meaning.

This event is called “how to treat your family”
It will be an important reminder when thinking about future relationships.

3. “Forgiving” does not mean forgetting
It's natural for you to think “I'll never forget it for the rest of my life.”
Forgiving doesn't mean erasing memories.
In Buddhism, “forgetting repentance (fubozange)”
A heart that never forgets the past and continues to learn from it is treasured.
You don't have to force yourself to “flush it down” now.
I stare at “his kindness” and “a word lacking compassion for my mother” at the same time.
Your honesty, having both of these, is the maturity of your mind.

4. Turn this event into a “kind of dialogue for the next”
Once you've calmed down a bit, try conveying it as a “meaning” rather than an emotion.
“I know I didn't offend you. But my mother was special to me, and the moment I heard those words, my heart tightened.”
By telling him that, you can give him an opportunity to learn “what respect is.”

5. Lastly
Through this event, you have deeply learned “what it is to love.”
The kindness of thinking about my mother and my desire to believe in him are both real.
Please don't be impatient and take your time to organize it within yourself.
Eventually, that pain becomes the cornerstone of “dialogue that fosters trust.”

Gassho

If he assumes that the word “deterioration” is a statement about appearance, it is likely that he was in some way dissatisfied or shocked by his mom's appearance.
For example, if your mom is quite fat, there is a possibility that his imagination (anxiety) about your future came up there.
For example, if your boyfriend's father or older brother is bald, women may think, “I wonder if my boyfriend will go bald in the future.”
There may also be women who just talk about that anxiety.
So, saying that may be the opposite of expectations (begging for nothing) that “I don't want you to gain weight (like your mother)” and “I don't want you to go bald (like your father).”
In other words, the reason the keyword “deterioration” comes up may be because my boyfriend is somewhat particular about the appearance of his romantic partner.
Buddhism explains that everyone always ages and declines, so deterioration is normal, but maybe he still doesn't know (not prepared) the reality that the four tribulations of life, old age, illness, and death happen to everyone.
In any case, I thought that in the keyword “your mother is a deteriorated version of you,” it is not simply an evaluation of your mother, but that your anxiety about your future (albeit unnecessarily indebted) within your boyfriend is appearing.
Obsession with appearance and obsession with youth is an affliction that causes trouble and suffering, but it can also be said that my boyfriend is an innocent (young) young man who is caught up in such afflictions.