Hi! @"Bon Bon"
Perhaps it is because Tamoxifen is at the end of everything else you've been through and the feeling of being overwhelmed by it all has accumulated to the point of where you are at now! May I suggest that you ring BCNA and speak with one of the Counsellors / Nurses on line - A conversation in private may just help give you some guidance!
Take care, sending you a virtual hug
http://onlinenetwork.bcna.org.au/discussion/17631/helpline-nurse-member-services-officer-available-tonight-on-helpline-1800-500-258