“There are those who look at things the way they are, and ask why... I dream of things that never were, and ask why not?” Robert F Kennedy.
Because we have been told this is not "normal", we question the "why". But there isn't an answer other than what Senator Kennedy said. Why not? Is there something there that is pathological? No. Is there something there that will make you a worse person? No. Is there something there that will lead to ruin? Yes, if you continue to fret and worry over it it will consume you. As long as you view this as problem it will be a problem. My advice is let it go, be who you are. You don't have to live up to others standards because they don't think you are right. These are clothes, they don't make you do anything different (if they do then you do need some help) than what you would do anyway. Society has set standards based on unproven and "expected" results. In the case of cross dressing these standards are totally subjective and the "expected" results are unlikely in everyday life. You have to take control of who you are and let the others worry about themselves. They are just clothes. They don't have magic powers. You don't slip into oblivion by donning a dress.
Why do you wear them? You wear them because you like wearing them for whatever reason you have. To be sexy, comfortable, to feel whole, to get attention, to feel power or to feel submissive. You wear them because you get some pleasure from them. Just like you eat chocolate or you get a new car or you sun on the beach in Acapulco. You like it, it harms no one, just do it. When the end is near you can be happy or you can be sad because you decided to follow the crowd and not your heart.