While the first 6 months were great, it seems lately that things are beginning to slide.

The sex life has taken a downturn, it feels like they talk past each other at times, her moodiness is irritating him more, and she is complaining about the weekends he sometimes needs to work for his job.

The emotional side is finding that you have a lot in common, that your views of the world are the same, that you share a sense of humor or like the same music.

Running along this is finding in each other what you most need – someone who listens or someone who seems decisive; someone who is gentle or someone who is strong and confident. One obvious danger or downside is that you never get beyond one or two dates.

Here is where what each person is particularly sensitive to – criticism, control, lack of appreciation, not getting enough attention – begins to stir: Chris starts to feel micromanaged, or Kara feels abandoned and is increasingly resentful of his working weekends.

Here is where couples can begin to argue about who is more hurt, who is too sensitive, arguments that can seem endless or destructive. Often by this time in the relationship real-life experiences become part of the mix and challenge.

Here they are: Stage 1: Oxytocin or bust This is where Tasha is at.

At this stage of the relationship, chemistry, both emotional and physical, is in the forefront.

What this all translates into for couples is the natural experience that things are settling or a winding down.

Routines set in, the hot chemistry is okay, but less hot.

Researchers have found that oxytocin levels naturally drop in couples somewhere between 9 and 18 months.