We have very similar stats, right down to gaining 100 pounds while being with an ex. I get a lot of this, I really do. But at the same time, my overall loss has been very slow so I think it's given my mind a better chance to adapt to all the changes.
To offer a look at the other side, my personal "normal" resides around 250-275 pounds since it's where I've spent most of my life, even throughout high school. When I skyrocketed to 360 pounds several years back I would have sworn I wasn't a pound over 275, but dammit, why wouldn't any of my old shirts or jeans fit? They must have shrunk in the new dryer! And why wouldn't the 2X's at the store fit anymore? They must be making the sizes smaller than they used to. Chairs must have been getting smaller too, as well as store aisles and restaurant booths. And what is up with my car's seat belt? If only I could see the part that I have to buckle . . . so yeah, I was seriously in that much denial until I bit the bullet and climbed on the scale. Aside from some growing health problems that I kept disconnected with the extreme gain, I didn't feel any different than I had been when I was 100 pounds lighter. In my mind, fat was simply fat anyway, so how could there really be a such a notable difference between my normal 250+ pounds and the 350+ pounds I so suddenly realized I was?
It took years to work my way down to the 250 range, and once I did, it pretty much felt like I'd accomplished nothing. I was still in plus sizes (although I could at least buy off the rack again), and I was still 100 pounds overweight. Woopty-freakin'-doo, right? It wasn't until I'd dropped to around 220 that I really felt I'd accomplished something amazing. I'd gotten down to a size 16, noticed I could
bend, and felt positively svelte. Even though I knew I still had problem areas and continued to carry most of my excess weight in my stomach, I was starting to feel like a "normal" human being for the first time and not just a fat blob. Sitting in chairs with arms is no longer an issue. Booths are never an issue. I can wind my way around most tight spots easily. Seat belts are a breeze! And for the first time I realized I could bend over to pick something off the floor and not be in pain, and not find it extremely difficult.
Being pregnant now has added an extra layer of issues on top of all this; my growing belly feels more like that old, "normal," 250 pound me. I keep imagining how much of a shock it will be to my system once I have the baby and lose much of this stomach; I barely had a chance to get used to a smaller me so it's gonna be like BAM.
Sigh . . . I wish I could offer more insight, but more than anything I think it's true that our minds often sit at where we've spent most of our lives. It'll take time to adjust, but it's ok. First and foremost concentrate on making your health a priority, and the rest will likely fall into place.
You've accomplished so much already!
You're gonna be fine.