Character development and maturity

Arnav always assumes that what he sees is right/true.He has always done that.Where is character development in this?

Khushi isn't mature because she never learns from her mistakes.How is arnav singh raizada mature then? He doesn't understand that there is always a tiny possibility that he may be wrong,on the basis of his assumptions he takes such ridiculous decisions.How is he a sensible character then? Khushi assumed that may be shyam will sudhrofy when the baby comes,so she decided to give him another chance.Didn't arnav do that too yesterday?Shyam desrves a second chance because khushi is now his wife.If shyam-khushi could have an affair while shyam was married,what makes arnav think that now they will end their relationship? The maturity levels may not be that shocking after all😆