Ishwari never took interest in Dev's life since childhood n neither as an adult. The parent(s) has to first build that bond with the kids so they share things with you n as they grow older they r in the habit of sharing more things with you. Thus Dev not sharing anything personal is literally Ishwari's fault. She always glorified her struggle even in her flashbacks. Hence Dev not telling about himself to Ishwari comes off as no surprise.
He believes Ishwari will support all of his decision. But unfortunately his decisions till date were all for his mother n sisters, never about himself.