I have been with DH for 8 years. We get along in a friendly and enjoyable way for much of the time, but we are not passionate, we do not say 'I love you', and we never have done, really.
I lurk on Mumsnet a lot and see how close people feel to their DHs, and I envy that. I do try to make a big effort to be close and affectionate, in fits and starts, and sometimes it works. Then we have a row and we seem to slip back into just getting along fine. We are ok as a team, I am not unhappy, as such, and I think he feels pretty much the same way.
Should we carry on like this? Try harder? Or be ambitious and make a break for the chance of something passionate with someone else? (which would mean breaking the DC's hearts, and have no guarantee of success).