I wrote half of a first draft a year ago and while it's good I can't replicate the same style anymore and don't know whether to scrap it.

I wrote something like 100,000 words a year ago and it's really good but ever since I got medicated for my bipolar disorder my writing style and state of mind has changed. I wrote it all in like a month and a half while I was manic and now I don't know what to do. I just turned 27 today and feel like a failure because everything in my life is shit and I've never finished anything I've written yet, even though I call myself a writer. There's gold in that first draft but I don't know if it will fit the rest of my style when I finish the draft. I've been trying all year to write another draft but I just can't because the old version is just so much superior than anything I've ever written before and it was while I was manic and I can't attain that same level of creativity anymore. I feel like hanging myself because even if I do finish this draft I don't feel anyone will like it. I've been working on this story for eight years now and while the story is never better (outline-wise) I can't finish a draft. I'm so lost.