What's in a name?

". . . that which we call a rose would be any other name smell as sweet." To quote everyone's favourite love-sick teenager.

Today, in a rather fancy email, I referred to Nick as 'my partner' today because referring to him as 'my boyfriend' didn't seem appropriate, it doesn't cover so many things like how we're 26 or that we pay bills together.

So, what do you call your significant other, if you're not married or engaged but are older than giggling as you hold hands in the cinema – because I can not find a term I like.

Other half – because without the other half you're only half a person?
Significant other – sufficiently great or important to be worthy of attention', doesn't seem to cut it really.
My better half – please. This just isn't true . . .
Ball and chain – just sounds restrictive and painful
Partner – too western. It also reminds me too much of Woody from Toy Story.

So, I'm just going to call him Nico.