I think this is something you get used to as time goes on <img src="/images/graemlins/smile.gif" alt="" /> I know when I was first living with my boyfriend (almost 7 years ago!) that it was really hard for us each to go off to work in the morning, since the thrill of being with each other was so new and fresh. We wanted to do absolutely everything together.
As the years went on, we still love doing things together, but now I also value having dinner just with my sister, or going out with just my best friend. In the early days I would have brought my guy along too, but now I appreciate having quiet time with these other special people, to be able to talk with them one on one. My life has more 'dimensions' that bring me joy, instead of just "him".
So for me it's the same during the day. I hug and kiss him when he and I part in the morning, but then he's at work interacting with his friends and getting a sense of "doing a good job", and I'm at my work interacting with my friends and also having that "doing a good job" feeling. So I wouldn't trade that for being able to have him sitting next to me the whole day.
The things he accomplishes during the day makes him more dimensional, and what I accomplish makes me more dimensional. So when he and I are both done with work at the end of the day, and get together, we have fun things to talk about, and fun accomplishments to share, and enjoy relaxing with each other.
So we send each other off with a smile, greet each other with warmth, but we both enjoy what we do during our time apart. We keep in touch to know when we'll be done with work, and what our evening plans are, but we don't wish we could run away from work to be together again ... we enjoy what we do for work.