Spicenitup07, It is a pretty common thing. Especially when you have a long term relationship that is secure. It took me 7 months to get over it, there is some pretty good advice in the archives of this site that really helped me. Last Saturday night will officially be kniown as erection night
(we had a Federal Election in Oz). Relax, enjoy, you've got other talents. When you're not worried about it, it will happen...it just takes time and in my case someone who we knew well and who is very desirable. All our playmates were extremely understanding and now look forward to the genie being out of the bottle.
Having your wife act as a "teaser" also helps, not only physically but mentally as it reinforces that she is giving her consent.
Good luck
Mr P & P.