First off, you don’t suck at this! You are using a CGM, you are asking for help and you seem to have a good handle on what the issues are. So you are way ahead of many out there! Give yourself a big pat on the back!
When my doctor asked me what my biggest frustrations were with my diabetes, post meal spikes was one of them. It is a hard one and takes work. For me, I use Victoza to help with those spikes a little. It also helps with appetite suppression so I don’t eat as much, so less spikes.
Another suggestion on carb ratios, it kinda sucks but you need to be eating the same thing every time you are testing your carb ratio. Using a frozen dinner is easiest because those are all automated on the production line. They do this when I am on a clinical trial and they need the same thing for each overnight testing. This way you can see if that 1:8 is correct or if you need less and 1:10 is better.
The other suggestion and it takes work, is watch your CGM. Most people who have nailed their post meal spikes have their pre bolus timing worked out. For me, 15 minutes works well if my blood sugar is in a good spot. If higher than I should be 20-25 works better. If less, 5-10. But if you have time to spend doing this, you just take your insulin and than sit and watch to see when the first dot heads down. When that first dot drops, is usually a good time to eat. And then see where you are 2-4 hours later.
You also need to have good goals that make sense for you and your medical team. Are you striving for 90% in range or are you good with 70% in range. I have found this is a moving target. For many years, I was good with 70% but with the Tandem Control IQ I strive for 90%. I am not making that goal right now, due to stress from work and COVID but that goal was agreed to be a good one for me and my up to now knowledge of the system. My doctor wou,d probably be ok if I said 70% but we both know, we can do better and for the most part we do. So having realistic goals is a must. Don’t try for it all. Just little baby steps. Pick one thing, figure it out and move on to the next.
I would also suggest some books, Think like a Pancreas, Pumping Insulin and when you what some more advance thinking Sugar Surfing.
Good luck! You’ve got this and keep asking questions!