Why? (Spoiler)

I think it mainly has to do with the fact that he was a manic-depressive, very eccentric, possibly schizophrenic. The drugs didn’t help, they made it worse but it wasn’t the drugs that drove him to suicide.

Fat, drunk, and stupid is no way to go through life, son.

I thought they were making him out to be a Brian Wilson type character but the suicide doesn't fit.

I disagree, teledyne. He's clearly going downhill beginning with the crazy music, then the paranoia when the tape gets lost & he brings in all that unnecessary security. Jonesy helps him get a little better thru some pop-psychology, and in that short period of being better he writes a beautiful song. Denise mistakenly thinks he is completely recovered and wants him to go out with her & Cheryl. But he is not at all recovered and that is why he walks into the sea.

I think it had a lot less to do with drugs and a lot more to do with being an artist and having that "voice of a generation" burden on him.

Are you referring to Dennis Wilson? Those in the know say that he was equal to Brian Wilson as a songwriter (though he didn't have the drive). He was the only surfer in the group, and unlike Brian, he died. Drowned.

<<I got the feeling during Jay's last scene with Denise that he knew 1) he would never be completely well; 2) she would insist on taking care of him or she would have to cope with his ups and downs; 3) she would never get around to doing her album and fulfilling her talents as a result. As Joel noted, Denise always thought the men in her life were more important than her work. By killing himself, Jay was sparing her (and himself) years of pain and giving her a chance to achieve her goal because he loves her so much. (It's a very similiar set-up to James Mason killing himself at the end of 1954's A STAR IS BORN, and for the same reason.)>>

I absolutely agree with you, deering 24. I believe the character was based on Brian Wilson (with some bits of Dennis Wilson, Jim Morrison and the James Mason character from ASIB thrown into the mix), but showing what probably WOULD have happened to Brian Wilson had he not been treated successfully by Dr. Eugene Landy in the early 80's. Don't forget that Brian's longtime first wife, Marilyn Rovell, was also a singer, like Edna/Denise.

If Carole King's first husband, Gerry Goffin, was ever involved with drugs I wasn't aware of it, and I believe they were married for a much longer time period than the characters in this movie. Therefore, the Brill Building background fits Carole King, but then it also fits Cynthia Weil and Ellie Greenwich to some extent, although neither has had a successful solo career. I think all of the characters are composites, of necessity. No one involved with this production wanted to be sued!

Can't believe the controversy over the Lesley Gore character! In view of Ms. Gore's disclosure about her sexuality, even those of us who are in the same age group as the performers this movie is based on are no longer naive and can easily see how that fits into the movie. My goodness, in 1965 hardly anyone who was straight would have picked up any of those clues, but I thought just about everyone over the age of 12 was pretty sophisticated in those types of things these days! Sometimes I mourn the lost innocence, frankly, and that is what makes this such a delicious time capsule of a movie. I love the music, and the whole cast is just terrific. Gotta get it on DVD now; wonder if there are any extras?