Stung by a Client?

Anyone out there had experience with selling commissioned work? I did a massive canvas recently for a client to close remit and with much client liaison. It took around 8 weeks part time to complete. She was delighted with the work both on completion and collection and payment. A week later - she tells me (as I drop by her shop noticing the work is not being displayed) that "would I be offended but..." she wanted to paint in "extra" flowers!!! In this instance it is likely I will simply disown the work and not actually paint in any extra flowers as an additional favour (paid or not). The composition is complete I have neither the time, nor inclination to "add" to it or alter it. She also took issue (belatedly) with two Maccaws pictured there owing to some kind of negative connection she'd discovered she'd had with them and wanted them out too (she thought, erroneously, that they were parrots!). I am considering asking for the deletion of my name, but I want the picture photographed (if she agrees to this, or at least sticks to her promise that I can photograph it as sold first) prior to any changes she daubs on. Any thoughts on copyright, professional conduct etc. The picture is NOT representative of any work I would consider being typical of mine - so despite the insult and the tremendous effort that went in - I guess I can let it go. Cheers all!