Apple Music keeps deleting my songs from its player, sometimes completely off my hard drive!

Apparently someone didn’t like my previous question(s)… I’ll ask them again in hopes they are answered and not ignored…

Why is it that Apple Music deletes my music from the library and sometimes completely off my MacBook Pro? Also, why does it randomly add music I never added to my library?

I have a private music collection consisting of music I’ve personally ripped from cd and things friends have given me. I have never subscribed to Apple Music’s pay service, nor will I ever subscribe to it. However, apparently subscribing to it is the only way I can sync my devices up… not what I signed up for when I paid $6,000 for my MacBook Pro! I thought I would be able to use it for what I needed, not have to continue paying for services I do not want and cannot afford.

Please help! I can’t find any info on the internet or Apple Community about it, because everyone seems to just ignore people when they ask about it or tell them they need to sync their devices (what they don’t say is that service only comes with the subscription to Apple Music).