Thank you all for your thoughtful responses. Your feedback helped me gather my thoughts and better present how I felt to DH.

And - HowLongIsForever - The first thing DH and I both told SS20 when he got the almost failing grade in the core class was: "why don't you retake that, see if they offer it in summer" We urged him to retake it for a higher grade. I told him it was important to show he understood the core concepts and that even if it put him behind a year it would be worth it in the long run. SS20 thought we were overreacting. He was very cavalier about it.

Since I posted last week I had a nice long talk with DH. I told him that I am concerned about how this affects me. That got DH's attention. DH agreed with me that if SS20 quit his job he would have to improve his GPA each trimester. If there is no improvement there will be consequences i.e. he will need to move out of our house, somewhere else, don't care where. SS20 will also have a list of chores to do, in addition to what he already does at our house, to contribute to the household. DH was also adamant that he was not giving him money or providing any more support than we already do, we will not fund date nights or car club or pay for gas.

SS20 has not brought up quitting his job since he first mentioned it. SS20 has also joined a study group and seems to have rededicated himself to his education.

~BettyRay