Everyone else has already nailed how this is not your problem. Just wanted to add- Even if you for some bizarre reason wanted to take on all the responsibility for someone else's life, you really can't do it for them. You'd be set up for failure. The only way to win is not to play.

Everyone's gonna immediately jump to "leave him!" But you should do what you want to do, obviously if you're the reason he'd wanna be successful then that must mean SOMETHING. If you want to leave him, then do it, but consider all your options.

wasn't she supposed to have raised him to be a self sufficient human being who knows his responsibilities? She shouldn't expect you to do it for him. He is a grown man.

But... you're not his mother, she is. Might wanna remind her of that.

Date me please!?!

That sounds like a compliment

See how much it's worth to her to keep him motivated...?

not your problem.

My son's wife's parent did everything they could to convince my son to marry her. They thought his drive would motivate her and stop her destructive behavior. Listen to what your gut tells you.

Isn't that supposed to be the bf's job to get himself into college?? And even it wasn't, it'd be more his mom's job then yours OP...