im 18 and i know a few ppl about my age who like bon jovi, but its certainly not a majority. the problem is theyre too hard for pop kids who like stuff like busted, mcfly, justin timberlake and maroon 5, but theyre not hard enough for a lot of punks, metalheads, hardcore ppl, etc. you cant keep everyone happy. i listen to a variety of music anyway - most kinds of rock, for example: stuff like da jovi (guns n roses, def lepard, aerosmith, the darkness, U2, etc), harder stuff like ac/dc, metallica and iron maiden, soft stuff like coldplay, travis and snow patrol, weird progressive stuff like radiohead, genesis, muse and the mars volta, and a lot of punk, from old bands like the clash and buzzcocks to newer ones like sum 41 and green day, and rock n roll bands like the stones, the beatles and the who; and other types of music like classical (which i play), opera, ska, reggae and funk.
i have strong preferences and opinions in music but i try to be open minded as possible - unfortunately a lot of ppl aren't open minded about music (or anything else!) and they won't try to see why you like the music you like. ive had a lot of shite from ppl who dont like bon jovi, especially when i was around 14 years old (people are very bitchy at that age!) but they often improve when they get older (say about 1

. if they havent improved by the time theyre 18 to 20, then theyre never gonna grow up, and theyre probably the sort of ppl who only listen to one type of music or one band, and wont try listening to anything else or trying to understand why you listen to the music that you listen to.
one thing to bear in mind if you are under your country's legal age for drinking: wait until you and everyone else your age is old enough to drink alcohol. then go to a party with alcohol and a DJ. when the DJ plays "livin on a prayer", everyone will sing along, especially in the chorus when they will sing it at the tops of their voices! even ppl who normally think theyre too cool to like jovi will join in. it is normally cos (a) theyre drunk so they lose all inhibitions, (b) they think everyone else is drunk so they think they can do whatever they like and everyone will be too drunk to remember it the next day, or (c) they just copy the people around them, so when they see ppl liking jovi theyll copy them.