I'd say a variety of veronica longifolia.

Thank you. I lost it and would love to replace it.

Not Salvia nemorosa then?

Veronica spicata? Don't think it's a Salvia, could do with a closeup of the flower.

Try checking the stem, Sue . . . all Salvias have 'square' stems.

It definitely wasn't a Salvia, "was" being the operative word,sadly. I really miss it. Sorry this is the only photo I have.
I've looked up several sites for Veronicas and found two or three similar so things look hopeful. Thank you all.-

Hi Stera, you may have sorted already, but sitting in garden today and noticed my new (this year ) veronica, although it has done its primary flowering, there is more flowers coming from leaf axils, and they seem to be of a similar colour to yours. the plant is veronica "Marietta"
this may help?? Cheers Kev

It certainly looks like it Kev, thank you. I didn't see that variety when I was hunting round Google. Where did you get yours?

Stera - here you are - http://www.hardys-plants.co.uk/product.asp?plant=2931

Thanks Andrew. My old one was in full sun on not very good soil so perhaps that's why it only lived a few years.

Hi Stera
this came from one of our local garden centres, as in Planters of Bretby (as far as I remember), just looked at the label and spotted www.bransfordwebbs.co.uk.
which may be the origin of the plant
hope this maybe of some help towards a solution, p.s. says full sun and well drained soil
cheers Kev

Brilliant. Ta muchly.