"Friendship is forever might well be:
Amicitia aeterna est.
"Friends forever" might be:
Semper Amici.
If all the friends were female, Semper Amicae would be better, I think.
"Live, Love, Laugh" is tough, especially if one tries to reproduce the neat alliteration of the English.
A literal translation, if infinitives are desired, would be
Vivere, Amare, Ridere.
Or if imperatives:
Vive, Ama, Ride.
Or if plural imperatives are desired:
Vivite, Amate, Ridete
Force to alliterate, the best I could manage would be:
Convivium, caritas, cacchinatio.
I am not at all satisfied with this. The three words are all nouns. Convivium can mean "a living together" in a broad sense, but usully means "a feasting together" or "a dinner-party". Caritas is OK. But cacchinatio usually means a loud , raucus laughter.
Maybe one of our colleagues can do better.