Depression after milestones/ Identity Crisis

So, I'm almost on day 320 of Weight Watchers so far and I've lost both a substantial amount of weight, but it's also the same weight I've lost a thousand times before.

Anyway, the other day I weighed myself and I'm at the lowest weight I've been in almost ten years. I have a long way to go, but I'm overjoyed and I'm glad I am sticking it out.

With all that being said, NOTHING prepared me for the identity crisis I just had for three days this week. I weighed in, saw my new lowest, started buzzing from excitement, calmed myself down because I had a feeling I could fall back into old habits and then all the sudden I was depressed.

Now, getting depressed after reaching certain milestones is something I've been through before. I'll get depressed for about three days, try to write, go to meetings, talk to some friends, etc. I just feel like the more weight I drop, the worse I feel for those three days.

It's almost like if I am not "fat" or "trying something new to lose weight" I don't know who I am, and it's bizarre! It's exciting, exploring myself, but also really strange.

I had moments where I thought about my mom, and my grandpa and what they would think or if they would like me after 600 days of WW or something.

I'm almost breaking a hundred pound weight loss. Usually I would reach 70 pounds and then hide away for a little bit to gain forty pounds back. It's surreal to think about.

TLDR: I lost a significant amount of weight and had a three day identity crisis