What if wife proves husband has an extra marital affair ?

thanks experts...

plz guide... on one more query related to this..

how to prove that we have been staying away since last 6 yrs and no physical/emotional bonding...?? what is she says, we have been cohabiting....it wud come back on me and very difficult to prove ... OR what if she says... i have been neglecting her ?? how to handle that situation....?