Well a lot of things and people pass through our lives from high school to 10 or 12 year later. Even if you were in the wedding the emphasis would not be on you, but to celebrate your friends new married life. Be happy for her and move on! I know, easier said than done - but your BF may be correct, and a few years since high school have gone by.
Consider taking an obedience/agility class or join the local Kennel club, maybe!
I totally agree with the dress, shower stuff