You have made it this far, you can keep going, the finish line is really close!
I am dealing with a new diagnosis, I am 32 years old and up to this point have never been able to finish more than two semesters of college, despite multiple attempts. I am in such a mess now and will have to jump through unbelievable hoops to fix it.
I GIVE YOU SO MUCH CREDIT for getting this far and realizing it’s important enough to you to keep going despite hardship. It is incredibly difficult when a routine or a comfort zone changes, and I can’t imagine the shock of your instructor changing mid semester. But you should remember that it was you who made it through the years you’ve already accomplished, not the professor. And you say you waited until senior year to get your life under control. That means you did all the years with your life out of control. Now that it IS in control, and you’re about to graduate, imagine what a dynamo you’re going to be in your new field!