It's an awful feeling when someone you love or respect doesn't approve or support your decisions.
I can't tell you how to get there or what to do but the goal should be if you're happy, making the right decision (to the best of your knowledge and experiences) and being true to yourselves....the rest will fall into place. Maybe you could try being very direct and asking why your shared happiness is not approved?
I'm guilty of spending too much time trying to understand opinions of others and end up putting their opinions and views before my own....denying myself of my own wants and happiness.....best of luck