Anitha, For me both Pei's marriage as well as Pei's illness both don't seem to be good explanations for TA's acting. But surely TA is acting as we see and Thulasi also has to be aware of it. The proper explanation may be TA is trying to find who are all involved in separating him from his beloved kuttiamma and that could be possible only by acting. At this time he may have only some vague ideas and it is always too much for anyone to believe mom and sister are traitors. This is because if TA really meant divorce with Thulasi, it is a really serious thing. T may be asked to tolerate yelling by TA because of Charu drama but T will never tolerate if TA meant divorce for real. Unless she has low self-respect. Probably this acting part was what TA and T were talking in the closed room. Unless TA is able to find the whole plot, these detractors could make a new drama. We are aware TA knows his mom and sister hiding the four lakh rupees. Still what they said could have convinced him and he has to find what they are up to.
As far changing Pei it is not his problem. There are many broken engagements in this World and if a man or woman has to do something for the person who is rejected, that could never happen. And TA is not a psychiatrist also. The best way he could have helped Pei is really totally keeping away from her and leaving her heal with psychiatry.