There are two main reasons I can identify with the feeling of not recognizing oneself...
First: I over-identified with my bipolar. I became immersed in mood cycles, meds, pdocs, fixing myself, triggers, and generally adjusting to life with bipolar. Basically I drowned myself in bipolar.
You know what was idiotic about that? I'd already been living bipolar for 10yrs before anyone figured it out, so I didn't need a new outlook on life
Well as I was drowining in my bipolarness, very little of me was recognizable, I was now this crazy person who had to adjust to being crazy... I didn't know her, couldn't know her, and for good reason, she wasn't real in the first place!
Second issue: I found myself on meds that muted my emotions, my reactions, my life experiences...
This was very traumatic for me! Thats when I started questioning myself, and realized I didn't even vaguely recognize the chick in the mirror
Now, some people can adjust to this muteness, some welcome it with open arms, and they fair just fine. Some simply need their meds tweaked to lesson it, for some therapy to help adjust to it, and this is perfectly ok if the person is happy with this kind of setup. Which I think most medicated members are...
This was not the case with me though.
I didn't like mute, I couldn't identify with mute. I was perplexed one day when something happened and I did NOT sob uncontrollably and throw things in my room

I couldn't understand it, and refused to accept it.
See for me (maybe because my bp has shaped alot of who I am, and I had grown to love that person) this was an unacceptable way of life. I cannot fathom going through life experiencing a fraction of my emotions when my volatility and sensitivity is an intrinsic part of my identity. I'd have to reshape years of growth and acceptance, and I didn't want to. Nothing about that option was appealing.
I wanted to be me again, I wanted to laugh so hard at stupid stuff I could wet myself. I wanted to be ecstatic just because, and be inlove with life so that I could have epiphanies and write gorgeous poetry, I wanted to hurt so bad I could bleed, I wanted to be me. The me I'd known and loved for so long.
I'm really really sorry about this long post, but I'm getting to the point, and didn't mean to make it about me.
Thing is this; there may be a myriad of reasons why you don't recognize yourself right now. Your job is to find out where you went, and provide a gps. If you have a T, they could be very helpful on this journey.
Maybe you just need to learn to adjust to the "new" you, or maybe you've gotten trapped somewhere just beneath the surface, and you need to learn how to emerge... 1 thing I find that helped to shine a light is passion. What is or was your passion, or atleast your favourite thing? Mine was/is music, but I lost that too. Listening to favourite tracks from years gone by was really like a time machine, it helped me with the first steps in getting re-aquainted with myself.
I'm really sorry for the lengthy post, I get carried away when I want to be as clear as possible.
I hope you find yourself soon