In my view dev didnt lied about his relation he is being practical. it hardly few weeks he has realised that he has fallen in love with sona. He was enjoying the fruit of being loved for the first time and to be with his love girl he just went to work late or post pone his meetings but he never neglected his work (he might have never thought about love neither during teenage or after he emerged in to successful business man; because its sona who made him realise about living a normal life rather than balance sheets ) . To be with his love of his life during day he use to work late night, but he never neglected his work, because he knew the value of work and money and he knew how many peoples life is in his hands. He was ready to face financial problems caused by signing Mr. Gujral deal but he didn't try to impose or recover that loss but choosed a different path by signing new deals.
Coming to the point of DevAkshi relation both are matured and they didnt took a step of marriage after falling in love immediately. Each of them given a space to explore each other, to know each other well, how they react or treat problems, they shared about their family( sona sharing about how Mr.bijoy bose spent money in shopping or dev sharing about ishwari, neha). During neha marriage seeing sona handling his family Dev realised sona is a perfect life patner,to him and also perfect family member, who can make his family stay happy and united.
After neha marriage for the first time dev and sona disagreed each other and the next day when dev asked wat to do (I felt dev was asking sona is she still ready to be with him, to love him, to stay with him) when sona said i love you and even though i disagree with u, I love to stay with you, which brought smiles and we can see from dev facial expressions, was relieved and relaxed with those words of sona.
Later dev sona wanted to share about their relation to their family, to present their relation infront of their family they need a proper time.
Just think practical when we realise that we are in love we just dont ruah to our parents and say maa i have fallen in love but i dont know whether im ready to marry her or him. We just take time and when we make a mind that she or he is perfect to share our rest of life we present our relation to our parents. The same has done by DevAkshi. After they fallen in love they didn't have enough time to think about themselves mainly dev because of neha marriage and worry for neha how she will get adjusted in ranveer family.
Presenting their relation infront of their family is not simple task for dev, for sona she has dada and elina to help and asha was ready to accept if sona has choosen any guy. Its dev, he needs a proper time to share his relation with sona to ishwari because love may be personal but marriage is not personal. Sona will not only be a life patner for dev but also a new family in Dixit family. He doesnt now how ishwari and mami are treating sona behind him. Previously he shouted at mami when she asked sona to mop the floor. Just a small hint dev needs, he makes everything. Perfect sona.
When the whole world chooses to rest after a busy day, dev tries to spend some time with sona, love of his life, when he is not getting enough time to sleep or spend time with sona then how can we ask dev to put his relation infront of ishwari. Till now he made his mind that ishwari and his family will accept his relation with sona but he doesn't knew the outcomes or present change in behaviour of ishwari. Dev once said that watever the decision he takes his family members support so he was confident that dixit family will accept sona.
For me dev didnt lied about his relation and its ishwari who knew everything about dev but not ready to accept the fact that dev loved a girl and ready to change himself which she was unsuccessful in doing it from many years. That point has hurt her ego. ishwari inorder to prove dev loves towards her, she is behaving rude towards sona. ignoring dev happiness ishwari want to compete with sona.
When an inseparable bond is shared between mom and children, mom gets to know easily about their children's wish.