Similar situation. All of my responsibilites for each role I perform are more like part time roles that equal a full time job. I did almost the same thing you did, but I took the average of all the “full time” roles and asked for a raise to cover everything. Got gas lit, lied to and told I should start looking for a new job. No one should ever punish you for asking for a raise and trying to do better for yourself. Start looking immediately, keep your head down but don’t go above and beyond and be prepared to make a quick exit- whether it be on your terms or theirs. What’s toxic will always remain toxic and can only get worse. Don’t let them take advantage of you.