Welcome to SR. I'm glad you've found us. Read the stickies at the top of this forum; they offer a wealth of information.
To answer your questions (and mind you, these are my opinions only):
1. He's out with the last bit of $$ you have, driving around to score dope. No, it doesn't get easier when this is the scenario of your life with him. It can get better if he gets into a program for his addictions. It can get better if you get counseling for yourself and work a program.
2. Will this ever stop? Only if he wants it to. I think you've found out you cannot make him quit. He has to want that for himself.
3. How can I help him? Don't give him money to buy drugs. Don't enable him. Don't give into his begging. Set boundaries and hold firm to them. Right now he's spiraling down into hell and taking you with him. We often have to step aside, get out of their way, and let them hit bottom. That allows them the choice, as an adult, to reach a point where they'll seek help.
You don't mention if you have children or if you have a job. Is he currently employed?