For me, I did not love the person I was. I treated her poorly. I told her she was fat, I told her she was ugly. I told her she was lucky she got her boyfriend when she was young and thin because nobody would want her in the state she was in now. I do find myself saying those things to myself, still, but not as frequently. It's a process. I have to remember to congratulate myself on my progress this far and encourage myself to continue further.
In the early stages of weight loss and change, it can be hard to see progress. This is when you may be in denial. This cures nothing, make this stage of grief short and gear up for the other four stages. Anger will wash over you at some point. For me, my internal monologue went something like this, "What the fuck were you thinking? It's your fault you got into this mess to begin with, you fucking pig." This stage actually helped with motivation, especially when I put some Marilyn Manson on the iPod...
Bargaining might be the worst part of mourning your loss. "If I work out extra hard this week, I can eat anything I want." Not so fast, Cowbella, that's not how this is going to work. Perhaps once you've reached a maintenance stage you can start to look at your food consumption differently, but you and I have a while to go before we have this discussion.
Depression. It's a bitch. The weight doesn't come off fast enough, you plateau, you can't eat at parties like everyone else. The good thing is that working out and sweating helps rid you of those feelings of sadness and black is a VERY flattering color.
Finally we come to acceptance. This is the longest phase, I'm still going through it. I think I finally started to accept my loss when I started purchasing new clothes and got rid of my "fat" clothes. You need to accept the fact that others will be treating you differently. The sad fact is that people are generally nice and more attentive to those who are healthier looking. It takes getting used to. People will want to talk to you and will smile at you. It can be a bit unnerving, and it might make you resentful at first, "Why am I acceptable now, and not before?". You just need to let that go, remember to be nice to those around you who might be dealing with their own weight issues, and accept that our society is built for smaller people.
Mourn the loss of your former self, but try not to be an asshole to your new self. She's much cooler and can kick your ass.
