John, most of the words used as technical names for psychiatric diagnoses also have common use meanings, and none of us can escape that.
Someone recently wrote to ask me about whether it was true that the word "homosexual" did not appear in English translations of the Bible until the 1950s. I double-checked, and let her know that quite simply it was not an English word until the beginning of the twentieth century, when it was coined as a translation of a technical term used in a German text on psychiatric abnormalities. Its transition into common use took a couple decades, and there were no major English translations of the Bible between the American Standard Version (c.1909?) and the Revised Standard Version (c.1958?), so it's not at all surprising that a word which had not existed at the time was not used in earlier translations. The point, though, is that "homosexual" still exists as a technical term in psychiatry despite also having a popular general meaning, and the two are not entirely synonymous.
I am depressed. Sometimes I laugh; sometimes I tell jokes. Depression is an undercurrent condition that is always there and has been for decades. Other people speak of being depressed when they mean no more than that at the moment they are sad. They don't really get the difference without some kind of explanation.
So I understand that you don't like the fact that the name for your particular clinical condition has a common meaning that evokes people going postal (a phrase which I'm sure the average postman finds very distressing), but you're not going to escape that by wishing everyone understood the difference between the technical and the general meaning. You might try telling people that you're "clinically psychotic" or that you "suffer from psychosis", which might be different enough when said that it causes them to ask what you mean by that instead of assuming they know. But saying "I'm psychotic" in the vernacular is a concise way of saying "I'm a violent and dangerous nutcase", so if you don't want that image, change what you say.
--M. J. Young