Ninad Ashwani marriage is not love marriage for sure , arrange bhi possible nhi lagta after seeing kaku & mast gang rant of Ashwani being from small family , so there chances r very less.
Before virat leaving for GC ninad told his story where a soldier sacrificed his life in order to save ninad like kamal sir did for virat & after that ninad took early retirement , I feel maybe Ashwani would be sister of that soldier who died or his finance , as some where ninad marries Ashwani out of pity coz soldier died coz of him , ya maybe nagesh chavan kaku's husband made ninad marry Ashwani .
This can be d reason of ninad keeping himself away from Ashwani & not supporting her further kaku made things difficult b/w them.
Ninad himself said he is getting pension , so I don't think he is dependent on kaku.
Indirectly ninad is responsible for sairat's wedding.