I apologize that no one has responded to your question sooner. Different experts come online at various times. I just logged on and saw your question. My name is ***** ***** I’m a biologist with a special interest in fish. I'm sorry to hear of this problem.I don't think you sound crazy at all. Many fish have delightful personalities, and I've been very attached to some of mine, too.
Average life span for parrot fish ranges from 10 to 15 years, so yours is certainly elderly. From what you have described, the bump is most likely a tumor. If it were an infection, the fish would not be active and eating well. Tumors in fish can be benign or cancerous. When they are benign, a fish can live with them for quite some time. If a tumor eventually grows to be big enough to interfere with eating or swimming, it may be best to humanely end a fish's suffering.
Right now, you'll have to make a decision. An aquatic vet may be able to surgically remove the tumor. The vet would have to evaluate your fish in person to determine if she/he is a good candidate for surgery. Age will be a factor in that decision. If you want to pursue this, this link will take you to a directory of fish vets:
The other choice is just to wait and see what happens. You may have seen YouTube videos of people operating on their own fish. It would be very risky to undertake that with an elderly parrot fish. If you want to try surgery I recommend having an experienced vet do it.
If you have more questions, just let me know. I hope that whatever you decide to do, it will work out well.
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