Passion fruit

So what is the difference between love and being in love. Is it passion? Is passion the missing ingredient in that recipe? I remember when I used to wonder and think about what my spouse was doing all day, where she was, was she thinking about me, was she happy. I do not remember the last time I wondered about that, or even gave it a passing thought. Is that the difference? Is wanting someone so bad you ache, that you see them and you just want to kiss them forever the passion that fills both your heart and your loins. Is that the being in love, or is that something else?

Thinking about it I find it hard to believe that my parents were ever in the in love phase. That they felt that way about each other. Maybe its because I am their kid and cannot see that or maybe its because they seem so far from that now, heck since I can remember they seem so far from it. Life is just a series of walking through things for them, at least relationship wise. I can see them passionate about the kids and the grand kids, but not really about anything else. Does anyone after they have been together for a long time still have the passion. Is it a silly thing to want, to hope for? I wish I had an answer for that.