First I'd like to preface this by saying that, as requested, I'm giving you my real opinion. I'm not taking the trouble to write this out to make you feel bad about yourself. I'm actually pro fat-acceptance, for people who don't have it in them or are happy with their body composition. Fat people deserve respect and compassion, just like everyone else.
If you REALLY want to change your condition, you need to toss that bullshit out the window and start looking at your condition as a problem to solve. Prioritize your success, not your feelings. I think a lot of great suggestions have already been made, and there are many paths to success, so my post will speak more to mindset.
You are basically in the exact same spot, at almost exactly the same weight that I started at. You even look like I did, assuming you haven't changed much since you posted those squat videos last year. And you are also right about the same "out of the box" fat boy strength level I was at, where I could handle 275 for 5 reps or so not too long after I put a bar on my back. I, too, had a litany of reasons and rationalizations for why I was fat. I blamed my long work hours, enabling partner, fat family members, stress, all the usual bullshit.
You need to sack the fuck up and fix the way you think about yourself and this whole process. That starts with the person in the mirror, not your mom or your dad or your relatives or Church Lady. Your condition is your own damn fault, and the sooner you can recognize this the sooner you can start un-fucking your behavior, one step at a time.
Our bodies are a product of the accumulation of individual decisions made over time. For a healthy and able-bodied individual, this is true no matter if you are very fat, very strong, very weak, very lean, genetically disadvantaged, or genetically gifted. The overwhelming majority of these decisions, the ones that REALLY matter, are 100% within our control. The first step in controlling them is realizing that you can. Like @T3hPwnisher said, you are simply prioritizing the choices you are presently making over alternative choices that will get you closer to your goal. Be very aware of this at all times.
Now we get to the good news. You don't need to be perfect, you just need to be good enough. When you are an untrained 320 pounds, your margins for success are HUGE. When it comes to improving your body composition by losing fat and gaining muscle, there is a spectrum of personal behavior that will determine your personal outcomes.
On one end of the personal behavior spectrum, you can be doing nothing right. You can be eating nothing but garbage, getting drunk, playing video games, eating all of the cheese, drinking straight maple syrup (Grade A Amber is my favorite) and living life from one seated position to the next while indulging in an orgy of unrestrained consumption. I've tried this at times, and the outcome is always fatter twojarslave. Always.
On the other end of the personal behavior spectrum, you can be doing everything right. Measuring food, hitting macros, sleeping like clockwork, training optimally and giving it all 100%. I've never pulled this off, but others have. Pro bodybuilders and high-level athletes live like this, or so I'm told.
That brings us to the middle, where you are doing some things right and some things wrong. Pretty much everyone lives here.
I've found that the key is to first identify the things you are doing wrong. This means being brutally honest with yourself. I've kept a log here for over two years, and in it I've chronicled both my successes AND my failures. The only thing I had to do to note my failures was include my bodyweight in each log entry. That alone tells a big story when you are really fat. Simply adding that piece of info to my log made me think about that number every day. For a long fucking time, I might add.
What you need to do is think about your own actions, and it is usually pretty easy to tell if the action you are thinking about taking, that you are AWARE you are taking, will get you closer to your goals or not. Church Lady offers you a cupcake? I won't say it is a "no-brainer" because the real "no-brainer" is acting on impulse. You need to STOP YOURSELF from taking the cupcake out of impulse, and use your brain to evaluate whether that gets you closer to your goal.
When you do that, you will start to learn that these individual decisions are really quite easy to make. Of course you should refuse Church Lady's cupcake, and tell her to fuck off if she gives you grief about it. Maybe you'd be more polite than I would, but what matters is making the right choice - right-then, right-there. Fuck off with your cupcake, Church Lady.
Think about all of the choices you've made recently, and then think about how often you STOP and really consider the impact they will have on your goals. You need to start thinking like this, one decision at a time.
The other part of this is building good habits, but this post is long enough already so we won't get in to that right now. You're already lifting weights, which is great. You definitely have fat boy strength, just like I do. You can leverage this to your advantage, if you start moving big weights week-in, week-out. You'll fire up that furnace of yours real fast if you can put a lot of effort and heart into your lifting. Keep it up, get better at it and don't quit on it. Just keep lifting no matter what. Even if you go off the rails on your diet for days, weeks or months. DON'T STOP LIFTING!!! OKAY?
I hope you found this helpful. I would really like to see you have success with this process. You absolutely can, but you have to choose success. You will either make progress, or not. If you are, great. Keep it up. Be proud of your good decisions, and enjoy the bad ones you are getting away with. If you aren't, you need to start thinking critically about your choices, just like we went over earlier.