My point is why does everyone hide things from Abhi and then give him gyan/ guilt trip if he reacts to the truth known to him. Again, PB hid from Abhi re AK giving therapy to MJ so that she can be shown Mahaan later.
In regards to Harshvardhan hiding Akshu.
Akshu had initially declined assisting because she was afraid she would just get blamed again for something she didn't do. She didn't want to go back to that type of environment but I am sure after thinking about it for a night she realized it was important to heal Manjari. She is a mother type figure for her after all.
If Abhi found out what Akahu was doing he would refuse Akshu to treat his mother. I am pretty sure even Mahima would object. Akshu is a music therapist and Harshvardhan made it clear in their conversation all options should be taken so there are no regrets. In the current state of mind Abhi isn't ready to distinguish between Akshu treating his mother like a patient and instead would see Akshu interfering in his personal life. Abhi is having a hard time separating professional and personal when it comes to Akshu. So keeping this under wraps was what made sense to Harshvardhan and Akshu for this particular situation.
Abhi keeps getting lectures because he unfortunately isn't in a clear state of mind. Everything is being seen through a particular lens by him. Even when someone is just trying to do good like Harshvardhan getting his music therapist daughter in law to treat his ex wife Abhi reacts angirly using his personal issues to vent on Akshu meddling in his personal affairs when they going for separation. He had interrupted Akshu before when she was giving therapy for his mother. He said some angry words that lead to that big fight at the Birla house.
Abhi's family has hidden a lot of things from him so I do feel upset with them as Abhi is acting out do to that. And if Abhi is in the dark Akshu is as well. She thinks she gave evidence that Abhi refused to use or look at. She has no idea Mahima and Parth are holding onto it. Akshu needs to apologize for leaving him in the dark for one year. I can only hope Manjari ends up talking to Akshu about that so she understands how this effected him. This could change the way she handles/reacts to Abhi bursts of anger.