[See Here: 1st Date vs. 21st Date]
Relationships are funny, they start in a particular way and end in a totally different way. And the journey is another thing to talk about. When you're going out for the first date, there's often some excitement and happiness. You dress well, you talk well and you put your best foot forward. For guys, they act all macho and offer to pay and be very chivalrous. But as the relationship gets old, you start getting more comfortable with each other and start losing interest in really doing something to excite the other. Here is a post that talks exactly about that. The difference between a first date and twenty first date. Check it out.