Hey kalinine if it makes you feel better my brother has been a vegan for years and also suffers from a painful gallbladder... but he also has high blood pressure. One thing that ties it all together for him is he is often angry/agitated/annoyed by others, and anger is related to the gall bladder meridian.
From The Journey to Radiant Health By Prema Key, Prema Scott Key
"The gall bladder is considered to be the official in charge of judgements and decisions. The gall bladder is in a central position to receive and release toxins. Thus, it is influential in promoting a state of calm and a sense of well-being. This is important because anger is the most toxic emotion, and excessive and unmanaged anger greatly damages your health and well-being."
Also wondering if you or the OP have done any kind of parasite cleanse?