healing other then the tank

[Zzyzxx71]

I believe what you're looking for is something like this...

/cast [harm] [target=focustarget, harm] PewPewPew; [target=focustarget, help] [] HealHealHeal

Assuming your healer has your driver targetted..

If your driver has a mob targetted, he'll pew pew

If your driver has a member of your team targetted, he'll heal.

If he's solo and you have a mob targetted, pew pew, if you have a player targetted, he'll heal.

Edit to your requirements if you use focus, which it appears you do.
I've used a variant of that in the past to heal individual members of my team without using 5 seperate macros. Works like a charm.