Communications with Apple may not really be Apple ?

How do i know if im communicating with someone at Apple ? I was fooled last year and gave remote 
access to my phone to a group of people claiming to be apple security but were not. 
The third time I talked and texted Apple screenshots of photos that just showed up in my email , pics of some disturbing stuff, a couple of pics of me hanging by my neck from a 
catalpa tree in my own yard. The Apple agent ,after she had seen all this and had remote access, said that senior security would call me first thing in the morning and I told her not to bother I had already talked to them twice and they couldn’t do anything. 
Then she tells me there is no record of me or my phone number or device ever communicating with Apple, ever. 
The first two calls went to a number in Austin,TX and I had googled the numbers and the search said that it was a legit regional Apple Corprate office, and they did the call with the recorded message saying that Apple would be calling in the next few minutes. 
I was on the phone with them the first time for two and a half hours and they had remote access to everything. I was completely fooled ,I had my Gmail,Google,Apple ID, Journal ,photo albums ,files,Amazon accounts  all taken and I was locked out ,Apple or Google nor Amazon would do anything 
to help. This kept going on and I still have some odd happenings. So is there any way to know for sure who I’m communicating with ? I reported all this to the FTC and it has pretty much stopped. I never was missing anymoney from anywhere. I found where I had been paying for someone else’s Amazon Prime account
for the last 12 months. My T-Mobile phone number had been forwarded to a number in Florida for how long I don’t know but T-Mobile wouldn’t help either. So is it safe to have communications with people and businesses on these devices?