Sorry to hear about your pituitary problems, but at least you know whats going on.
There is definitely information about long term low testosterone taking more time to recover. For example this study (
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5754577/) shows Androgen Deprivation Therapy (ADT) patients with longer than 18 months ADT took 9.7 months to recover, while patients with less than 18 months ADT only took 6.8 months for the same recovery.
The explanation about why that happens its my own thesis, so thats definitely not certain heheh. Take it with a grain of salt.
About the abscesses, who injected you? You need someone experienced in injecting this stuff. If its just your body fighting a foreign substance if you surgically remove it you are removing the actual nebido. If its not nebido related what is it??