Artists are people, they do what people do. They're not tragically misunderstood geniuses who cant connect with "normal" people. They get married, they have friends, they put their pants on one leg at a time just like everyone else.
I would say the ideal partner will support your career. If they dont, then that is a problem and you shouldn't marry them. Pretty simple. Artists marry other artists all the time, but its not a requirement for happiness that both parties must be artists to love and understand eachother.
Of course, before you consider marriage it is my opinion that you are in a well founded career so I would worry about that first before a wedding. You're 15, you have all the time in the world to get married and settle down. Concentrate on your art first and get into a good job. If you meet a nice girl or boy and they are the right one for you, then they should be willing to wait and support you while you get your feet on the ground.
"Astronomy offers an aesthetic indulgence not duplicated in any other field. This is not an academic or hypothetical attraction and should require no apologies, for the beauty to be found in the skies has been universally appreciated for unrecorded centuries."