I know someone irl who chose the name Luka and doesn't get many questions about it.
When it comes down to it, it's your name, and if it's not one you're happy with you'll either have to deal with it for a long time or change it. Try to find a name that suits you, and not one that suits the people around you.
Good luck in choosing a name and with family, hopefully in time they'll learn to accept.