Suppose one day you believed that only you (or in my case, my) mind and thoughts were all that existed or could be proved to exist. Suppose now the next day some event occured that so profoundly affected you that you doubted whether you had the strength to withstand the consequences. If so, does this mean that you (rather, me) am destroying my own world by imaginging an outside force, an imaginary Shiva god wrath, or maybe it is my Freudian Death Instinct come to bear, or does this mean that my solpsistic philosophy has betrayed me and proven itself incoherent precisely the day after I decided it did not matter if I was right or not, whether I was alive or dead, that everything seem so ethereal anyways that existence was such a subjective matter as not to deserve considered debate about.
If so, either I have met with the anti-solipsistic equivalent and we are mutually self annhilating, the me that only is, and the other that is everything but me, or I have been wrong all along. Either you will be able to bear witness or I won’t.