Why are voice memos and received text messages disappearing from my phone and computer apps?

I have an iPhone 5s running on iOS 11.1.2.

Some background: a loved one of mine died a year ago and I have been trying to access some important information that I had stored from/about them. One set of items is a collection of voice memos that I recorded during our last conversations. I had them on my phone for months, and imported the recordings to my Macbook Pro to keep them safe. Weeks later, knowing that my recordings had been safely transferred to my computer, I deleted them from my phone. I did not get a prompt of any sort saying that deleting the recordings would delete them on all devices, as I typically do when deleting an item that is stored on the cloud, so they were deleted and freed up some storage.

But recently, I tried to access the recordings on my computer and they were completely gone. My other less important recordings that had also been deleted from my phone were still there, but these ones I no longer have. I know they were on my computer at one point because I referenced them. Not only is this heartbreaking because it was a record of my last conversations with this important person in my life and I feel like I lost them all over again, but it is also incredibly frustrating because this secondary loss is due to untrustworthy technology and it was out of my hands. Yet they are not in my Trash and recovery software has not unsurfaced them either. They were probably deleted months ago at this point so it's not even something I can pinpoint.

In addition, I have also tried to access text messages from when this person was dying, and I now only have one-ended conversations. For instance, any messages with my father from over 6 months ago are all one sided; they only show my outgoing messages and I have zero record of received messages from him. Where did they all go? Why was I not notified that these were being cleared out? Why is it that some conversations still have received messages from that time while others don't? For the record, I have never turned on the "Delete old text messages" option because I don't trust any auto-delete settings. I'd rather approve each thing that gets deleted.

Overall, this may be the final straw with Apple for me personally. I don't appreciate how dependent I am forced to be on iCloud. For instance, I have an older phone that doesn't have a ton of space because they didn't come with much space back in 2013. For the last four years, I have regularly hooked up my phone to my laptop with a lightning cable and imported all of my recent photos. I then delete all the photos from my phone so I have space in the future. Now when I hook up my phone, I can't import my photos because they are all supposedly safe in the cloud already or in the Photostream. Yet, if I want to delete any photos off my device to have more space, a prompt tells me that they will be deleted on all of my devices so I can't.

Others have pointed out that you shouldn't have to delete them because with iCloud and "optimize storage", the photos are no longer stored on the phone and are instead on a server. But then I run into the problem that my photos have to load before I can even use them. I run the social media presence for a small business and have had countless occasions where I haven't been able to post content because the photos that I took literally moments ago are already off in the cloud and aren't loading on Instagram or Facebook or even a photo editing app that doesn't require data to use.

The catch-22: I can't turn off optimize storage because, again, my phone's storage isn't large enough to download every single photo I've ever taken. In order to make more space to download, I would need to delete some photos. But if I delete photos, then I delete them from every single device they are on and lose them forever.

I've pretty much given up at this point and am just assuming that all content on my phone will be subject to loss because I can't seem to keep things safe from auto deletion. But I'm appealing to the community as a last ditch effort for fixes. I understand if there are none and this was just a semi cathartic rant.

1. Have you ever had voice memos disappear from your iTunes account? Were you able to recover them? How?

2. Have you ever noticed old text message conversations missing half the content? Any fixes? I couldn't find a topic about this and its a shame that I can't download all of my conversations to keep content safe.

3. Does anyone have advice on how to more effectively use iCloud so I'm not stuck in this Catch-22? If I can't figure this out, I may need to suck it up and switch to a different type of phone because it has become such a time suck/nuisance.

Thanks so much for your time.