I feel for you. I've had some chemical burns from over-ambitious use of anti-aging products, particularly acids, and they can be difficult to heal. The longer I use Retin-A, though, the less I find myself needing to use acids at all...which I prefer. I use acids only occasionally in the summer now, and not at all in the winter.
If I'm understanding your post above, you're mostly concerned about dark spots?
For hyperpigmentation, there are a couple of things you can try, that aren't necessarily harsh. Vitamin C serum can lighten slightly, and it also gives a nice glow to the skin. PSF has an effective Vit C product that is mild. It's expensive though ($45 for a bottle that will last about a month), so I make my own with L-ascorbic acid, distilled water and hyaluronic acid. There's a thread about it over on the makeup board:
RCW - Homemade Vit C serum?
DianaYvonne.com carries a comparable Vit C as well. They also carry a natural lightening product, called Wildberry & Kojic Acid Serum, which does help with lightening also, and it's not going to tear up the skin.
Both Vit C and Wildberry/Kojic will help age spots only just so much. For real help, you'd need to use Tri-Luma, an Rx product which contains Retin-A, Hydroquinone 4%, and a topical steroid. That will really knock out the dark spots. It can only be used continuously for about 8 weeks though. I used it for that 8 week period, and my dark spots along the jawline and upper lip were gone, and now I use it once weekly for maintenance, and along with Vit C and regular use of Retin-A (and careful use of sun protection), I am able to keep my hyperpigmentation under control.
I purchase Tri-Luma from Mexico through mdmexskincare.com for $55 (plus $10 shipping), for a 15gm tube. That's where I buy my Retin-A from also." - RedCatWaves
Thanks for your detailed reply! I know, this has been a real challenge. I'm STILL spooked, 5 months later - and still cannot even wear sunblock, so any skin lightening efforts would surely be wasted without it. This is why I have virtually almost given up on the whole deal and kept things simple. The only thing I did recently was to re-instate a cleanser I used a long time ago that I liked which exfoliates very well without bothering my skin. I know it is detergent-based, which you recommend against, but somehow on my skin it is OK. I've tried natural non detergent cleansers and never felt like my skin was really clean plus they tended to leave an unfortunate residue.
I've tried homemade Vitamin C, very similar to your recipe, but it did nothing for me except make my skin feel sticky, no matter what I did to make the formula, or even with waiting a full 30 minutes after application to apply anything else. Even when I was using the Skinceuticals C+E Ferulic which so many people rave about, I thought it did nothing except moisturize a little bit, and for that a plain moisturizing cream will suffice. I guess my skin simply doesn't respond to C. I even used it for a few months too, working off those C+E samples too, and as I say, my homemade C didn't work out either. I wish it did, because I have the ingredients. What am I doing wrong - should it be really sticky? How do I address stickiness? Nothing seemed to go on right over it either. I hate to sound difficult, but this is how it is for my skin. Either it absolutely hates something, or something that gives great results for other people does absolutely nothing one way or the other, no in between. The best I can hope for is that something doesn't bother my skin, and cleanses and moisturizes it. I'm on a very low budget too, so that doesn't help. I can't spend $55 on one item for skin care. More like $10-20 is more like it, even less is better on my budget, and I don't want to have to special order something online either. I prefer to work with something I can get locally at the drugstore, health-food store, etc.