love we can't write defination of love but as per knowledge and what we see in world we can make it,
1) for all age love definition is different. like for young they think attraction means love. check science book.
2) middle age - friendship , understanding, caring, sharing, and also physical relation is love.
3) after 45-50 - support, sharing thoughts , caring , friendship, speding time for each other , and also many things that called love.

and yes true love never die is alive till he/she die,