Honesty and/or the lack of it is one of the biggest factors in relationships today. Too little and trust issues arise, too much and you risk over sharing. Theres a delicate balance to be had. But at its core is one fundamental thing, the first person you must be honest with is yourself. Lying to yourself or about yourself sets you up for a fall you may not recover from. Mis-representing yourself doesnt engender trust. Theres a saying in showbiz magic that states that once one part of a performance is seen as false then the whole thing falls apart.
Same applies to a carefully woven lie, remove one card and it all falls down. Therefore before presenting yourself to the world be sure its the same person you see in the mirror. If you can't be true to yourself, well... thats a problem.