Deaths/Endings/Goodbyes are extremely painful & distressing

I am not sure if this is the right forum for my issue but if not, perhaps the moderator can move it for me.

It has taken me many years to realise that I get extremely distressed at goodbyes, partings, endings, deaths, even for people I don't know and never will know.
This can happen in any form, including when watching a movie and sensing a death, a goodbye, a going away moment is coming up. I cry EVERY TIME with my body shaking and me feeling terrible pain.
I'm welling up just writing this.

I have a sense that this is to do with my early childhood and I have parents who were and still are emotionally absent/unavailable. There's no real warmth there. I have a surface-level only engagement with my parents (the weather, how are you doing, what's new, etc. but nothing much else). I think my parents might have had childhood trauma themselves.

I must have learned at any early age to not go to my parents when I needed something, like help, advice, a problem, etc. I don't know why but I remember withdrawing from almost everything as a child. I am still withdrawn and prefer isolation and being away from people generally.
My father also used to beat me when I did bad stuff, got into trouble at school or with the police.

As an adult, I have never believed I can be comforted by others and I do not even know what comfort means. I mostly think of it as fake problem solving or fake reassurance (which I can't stand), when the issue etc., is still at large or hasn't been dealt with.
I think I did not bond with my parents, which if true, is probably at the root of my feeling as I do about goodbyes, deaths, etc.

This issue is so great that I choose not to start anything with people, because at some point, it will end and any pleasure gained is massively eclipsed by the pain of the end.

I am OK with non-personal people contact but nothing else. I only want to stop myself from being affected as I am, but not to get involved with people.

Any suggestions as to what I can do about this?

So sorry you're experiencing this.

It seems like you're very insightful & introspective to understand the root cause of you feeling this way about goodbyes/deaths.

I don't know your experience growing up, but I imagine your parents do love you a lot, they just don't know how to show it? I had a period of time when I felt like my parents were some type of supervisor rather than a parent, but I do feel like that comes from it being hard for some people to communicate their feelings. It's way easier to just remain on the surface level of talking about what's new etc.
That being said, this upbringing appears to have caused you a lot of trauma. I think what you probably needed was love that wasn't held back. I feel like that's what you need now too.

There's a saying 'it's better to have loved and lost, then never loved at all.'
I firmly believe this to be true. When you're fresh out of a break up, it might be hard to believe, but when you're in the relationship and once you've moved on, you can see the truth in it. It also leads you to find your life partner. If you never put yourself out there and open yourself up to potential loss, then you'll never learn what you need from a partner and what doesn't work for you. And you'll never meet your life partner either.
Life is a very bittersweet thing. But there is so much beauty in it that a lot of people take for granted. I think you can take the lessons you've learned from your upbringing and create a life with a lot of openness about feelings, and with a lot of love.

Pushing yourself further away from everyone is only going to make things worse. About 100% of the time doing the more difficult thing in the moment is better for you in the long run, and actually makes your life easier overall. If you avoid pain or the potential of pain, you are avoiding having a life itself and are actually making your life more painful ironically.

So my suggestion is simple and I imagine you already know this is the answer; to open yourself up to making friends & losing friends, to starting relationships & losing relationships. On the other side of that fear and pain is love and happiness. But you cannot let fear of pain dictate your life, it will still be painful that way just in a different kind of way.