In medicine we are taught that the first line treatment for insomnia is treating the underlying illness—in your case, potentially depression— otherwise, CBT-i (cognitive behavioral therapy - insomnia).
So my first recommendation is to seek care from your physician for your depression.
Otherwise, there are well described self taught classes for CBT-i. I have told patients to check out the VA’s website for this: https://mobile.va.gov/app/cbt-i-coach
It is a lot of the sleep hygeine described in another excellent post hew.
I’ve always liked thrombophlebitis. Not happy when a patient develops this, however