As someone who's been thru the depression wringer for most of my life and on and off almost every med under the sun... I can relate to both of your stuggles.
Here are my personal thoughts hopefully you find them helpful and constructive....
1. For most people meds alone are not going to solve much. If they work even in the slightest, then hopefully are a boost to be able to learn better coping mechanisms and behaviors. This is done thru therapy and extensive self reflection. Like you said someone must be willing to get help for this to process to begin. also she needs to be able to see how her behaviors and thoughts may be skewed. This is difficult and very humbling for anyone to acknowledge and face their inner demons. It can't be forced or rushed it has to come on its own. And for many of us it is a life long struggle. Hopefully your wife is able to start getting help soon
2. See if your insurance covers or pays for at least part of a genome test. I just finally was able to have one done this yr. And the results were both disappointing and enlightening. After a lifetime of not understanding why the meds never helped or just made me feel worse...I found out that on a genetic level lack essential enzymes to process over 90% of all psych meds. And that anti depressants inhibit this metabolization therefore making it completely impossible for anything to help! . My point is I wish this was known yrs ago...it may have changed my life for the better rather then for the worse.
Hope this helps. I would like to address you and your daughter a bit more but I have to stop writing now. But please protect yourself and your little one as much as you can.