Hello,
1. Is there any expression for your boy/girl friend of the following?
eg you have been going steady for 3 months. He/She usually says to you "I really love you", "I can't live without you", "It's still afternoon but I'm driving you to home since around here is danger", "If anything wrong happened to you, do call me soon and I shall come to you soon", "Have you spoken to other boy/girl today?"
You never hate him/her but you feel the love is kind of bothering, annoying.
Can you say "He/She is very heavy", "His/Her love is so heavy", "I carry the weight of his/her love" etc.?
2. About Beatles' lyric, I Want You (She's So Heavy), does "She's so heavy" mean "She's so cool"?

The first question is kind of weird but I would appreciate your help.