Sorry but i have a diffrent pov.
So you came to know that your husband lied to you about being pregnant. He let you talk like a lunatic to an imaginary baby and kept on lying and lying about your pregnancy. And you expect Sona to be understanding?? She just came to know she cannot concieve and she needs to thank Dev for still exepting her?? Instead of breaking down and be angry she should right away praise dev for his mahaan act?
Why did he need to lie that she is pregnant?? When she did the test he could told her right?? That the test was negative. Why did he lie? He lied because he saw Ishwari change by this news. Everything became the way HE had dreamt about. Ishwari exepting Sona as her own. So how do you call this selfless love than??? He lied for his own good.
If he had told her right that minute after the test that she is not pregnant and told her about the infertility, then i could believe he did it for Sona. Than i would say he kept a secret anout infertility for Sona happiness. But he kept lying to keep ishwari fake love towards Sona intact. It was a convinient situation for Dev.