Arctic Mama said it all very well.
Losing the first 40 pounds was especially hard on me, since I was so relatively large that couldn't tell one lick of difference in the way my clothes fit! And even the first 100 pounds, although it's such a substantial number, still felt difficult since my sizes went down soooo sloooowly and it got me back to the "normal" range of weight I'd already carried most of my life (ever since my freshman year of high school, I was typically between 250 and 275 but went up to 360 a few years back, so the 100 pound loss left me back at 260). Being near the halfway point but still at an old set point made it feel like I was just beginning, and I struggled when I hit a low of 243 last year, completely losing it due to a lot of issues out of my control, and I mindlessly climbed all up to 267 before telling myself something needed to change.
I bit the bullet this year and promised myself that I was making healthier choices through eating more carefully with proper portion sizes, no matter what. Focusing on the amount of time and effort it's going to take gets rather depressing and overwhelming, but hypothetically speaking, even if I was at my goal now, this is the way I have to eat for the rest of my life. Might as well just eat with good habits anyway, right? The rest will take care of itself when you do.

Not just your size of course, but any related health issues, the amount of energy you have, and just the way you feel period.
The number 250 actually seemed like a magical crossover for me, since whenever I get under that I actually start to feel "normal." And of course that's different for everyone, and in my case it may just be because I'm not used to ever being under 250 (this is currently only the fourth time in my entire life I've been anywhere under 250, not counting my childhood, and I'm 36). I'm still clinically obese of course, but clothes definitely started fitting better for me. I can comfortably wear shorter tops now! Nothing that shows off my belly, but it's something I'd never even thought about before. Right now I'm sort of on the edge of plus sizes, occasionally able to fit into clothes from the "normal" section of the stores.
(See, shorter shirt!

)
For the record, I still hate my stomach. I'm an apple and it's the most stubborn part of my physique! I've often noticed I'd be able to wear much smaller jeans if only my stomach wasn't in the way (until recently, most jeans cut into my belly painfully while being insanely huge in the thighs and butt). Yet as frustrated as I still admittedly get, I also know that I'll never get anywhere near my goal if I focus on that frustration. Focus on the positives whenever you can! Think about how well you're nourishing your body rather than feeling like you're missing out. That was probably my biggest personal hurdle, letting go of the bitterness that I couldn't eat "like everyone else." Just keep up with the positives and actively make healthy choices, and things will definitely get better.
Hope this helps!
