I never thought Ricky was a stalker. He just marches to his own drummer, and lives life by his terms.
Look at his relationship with his father. He knows that instead of fighting him, as most people might do, he plays like he agrees with him, which keeps his father off his back, and leaves him to live his life the way he sees fit. Ricky will always make his way in the world, as he has learned the secret of getting people to see him the way they want.
However, I don't believe he is a phycopath. He feels beauty, he feels love. He doesn't stalk Jane, he patiently waits for her to come around. He's just eccentric. I just looked up a character analysis of him, and the term schitzoid came up. Personally, I wouldn't call him that, he's just different. In my mind, he and Jane are the most mentally healthy people in the movie. Not that that's saying a lot.
I also don't think Jane was just wanting attention, she truly appreciates Ricky for who he is.
Finally, I never got the impression she needed Ricky as a male per se to help her find acceptance of herself. She needed an example.
If this is for homework, I don't know if my interpretation is correct. It's just how I feel about those characters.
I also don't know your age, but this is definately a film that should be watched several times, time years between.
The feelings and thoughts it would evoke would be very different in a 16 year old, a 22 year old, a 30, 45 and 55 year old person.
I'm at the upper range of that, at 57. I first watched the film when it came out, when I was in my mid 40's. I see it quite differently than I did 15-17 years ago.
Doubtless, I would have gotten a completely different interpretation if I had seen it as a teenager, or a 30 year old.
Not saying it's impossible, but I would think it would be more difficult for a 20 year old to feel what the wife, or husband was going through. At the same time, watching the neediness of the best friend comes with a completely different level of understanding depending on your age. Some people might have forgotten what it's like being that age, others will remember.
For what it's worth, it's a complex film. Don't sell it short.