No experience with it but I reckon your doctor doesn't understand the complexities involved with mental health.
Can I ask, what did you want to receive from the infusions?
Perhaps you had built your hopes up and ended up disappointed that nothing has changed which could be contributing further to you wanting to die.
There are a lot of studies done on this and it's not always as promising as newspapers say with their headlines "Ketamine miracles" or something else a bit bizarre. But here are some articles and the subreddit has information which might be more useful to you.
pmc.ncbi.nlm.nih.gov
Intravenous (IV) ketamine is an effective therapy for treatment-resistant depression. A large data base is confirmatory and steadily expanding. Qualit…
www.sciencedirect.com
There's also a subreddit:
https://www.reddit.com/r/KetamineTherapy/
I'm truly sorry to hear that your body isn't responding in the way you and your doctor expected. I do wish you the best.