I've found taking my measurements and regular progress pictures help a lot. It really can be hard to see the difference in the mirror at times. It can even be exasperated if you're wearing the same clothes as before because baggy clothes can hide a lot of the weight loss.
So every 10lbs I take progress photos wearing the same outfit (a stretchy workout outfit so it'll last awhile still) and that's really helped me to see where I'm losing and the difference! Full length mirrors help too. We don't have one at home but there's one in the bathroom at work so I'll really look at myself at times and try to pay attention to where I've lost to update the image I have in my head.
Body image issues after significant weight loss are certainly real because it does take time for your head to catch up. But it does happen eventually! I no longer feel like I did in the 200's. I'd say my head is now just 10-20lbs off.
Size inflation doesn't help matters either because you might have a perfect size in mind that you always wanted to be and once you get there you realize that it's bigger than you thought! I was a size 8 back in high school when I weighed 140lbs... this time I started wearing size 8 at 175lbs! Quite a difference. Now I'm into 6's and even though the number is smaller than I ever wore before, I know the feeling is not where I want to be at. It was a bit upsetting when I realized that I no longer had that number to shoot for and I had to figure out a different goal. I still don't know what size I want to end up being because it's hard for me to judge. I'm guessing I'll end up as a 2? Maybe 4, depending on where I lose the weight and how much further I decide to go.
The whole journey is a crazy one but I have to say I do feel a lot better without that extra weight. I have more energy and it's helped give me the confidence to change other areas of my life that needed changing.