The only things I can suggest that haven't been mentioned already:

Try wrapping her in muslin or whatever you use, and then popping her in the sling/carrier (what do you use?) if possible. Obviously making sure she's safe. Once she's asleep, the transfer from carrier to bed/cot shouldn't be as noticeable for her. Used to do this with DD.

Do you have a white noise app or anything like that? DD has some sleep music we play really low in her room and also while we put her to sleep that seems to help.

you poor thing. I've been there too and you really can't see a light at the end of it all. I found when it got really bad, just giving up and getting up was the only option. DH was a great support too. I so hope things turn around for you soon.