"Bless you brother"
"God bless you"
Or "fortunes" for the less religiously inclined.
"You are so fortunate"
"May you have good fortune"
...and all the other variations on those themes.
Basically we are assuming that a greater power has the ability and desire to favour some people more than others. We believe we have the ability to increase the odds of this power's favouritism by speaking it out in some form.
We only need to ponder this for a minute to realise how absurd it is.
However, its done with the best of intentions, and we do hope for better circumstances for those we love, and to convey friendship etc. So it's not a bad thing when we consider the intentions.
But when we use these terms, we are reinforcing the idea that God (however we view it) is separate from us, and can dish out good/nice/loving/favourable things on a whim, if asked properly, or we do something good enough.
Perhaps we would be better to simply be thankful, to honour people as human, from our heart. Maybe we shouldn't declare them blessed or fortunate, but rather praise their humanity/kindness/generosity/selflessness... all the things that really matter and "build each other up in love".