How do you get him to listen to reason?

Pup said this yesterday : 10% of what you throw at them sinks in. So, while your efforts and truth darts and good exampls may appear in vain they aren't... Tiny Tiny steps are made in your favour when you attempt to educate a wayward spouse.

He's not in an affair I don't think... Otherwise I would say its only 1% that sinks in if you are lucky.

I think You need to write down some boundaries and expectations and make them known :

a. If he lives here, he does his homework and makes a sincere effort
b. If he leaves, you two will be pursuing divorce - no friendship will follow
c. No trolling facebook for alternatives/parachutes - I heard it called "lifeboating" once which I think is the best characterization
d. No talking to friends and family about marital problems in secret
e. No hiding of cell phones
f. No internet activity that risks harming any family member - even what they don't know CAN HURT THEM

etc...

This is a contract of sorts you two would both be accountable for if you choose to allow him to stay

I think It's also important Sunny that you word things as forcefully as possible here...

He doesn't know how to drive a marriage. If you put him behind the wheel this is giong right into a ditch... Don't leave it up to HIM to leave or to stay. You say it like "If you are going to participate in this marriage you are welcome to stay, otherwise lets pack your things and you can go now."

It gives him only two choices

work
get out

THAT is I think the best way to handle him.. if you wait for him to make choices and put firm sticks in teh sand he won't... he's going to obfuscate like almost EVERY wayward does... he's going tos ay he's trying, but he's not, he's going to stay there, and then not, etc... He will be all over hte place if you allow it.

Phil McGraw makes a very important part in RR - "You teach people how to treat you. You allow people to treat you badly."

if you throw him lines like

"Are you going to stay?" It gives him teh steering wheel. If you say "You are welcome to stay if you are willing to do the work" then he's forced to cooperate

Wording and intonation is very important.

There are more boundaries you have to set. That list of bad spirits can be a good start :

a. No drudging up the past - wasted money or affairs - both of you get a clean slate
b. No score keeping - You both contribute 100% to the home - salary or no salary
c. No secret-keeping - Smoke and Mirrors belong on the stage - you aren't David Copperfied so don't waste my time

etc