Honestly, if you want to keep the marriage, you really should live together. An 婚內的協議 will not work. (Even I am a woman, I won't blame the hu*****and too much for what happened. Not sayint he has no fault, but, he does have his reason...)
About 婚內的協議, I think the easiest way is to ask your hu*****and to put all his money into your own bank account, which has beneficiary as your daughter; and give up the claim to your house and etc., NOW.