Suicide is widely considered to be an act of cowardice. The fault with this argument is the presumed generalisation of the circumstances in which suicides are committed.
A suicide committed to escape from a dull / boring / screwed-up / bad, etc. life (as is generally assumed to be the case) may be remotely considered to be cowardly (although arguably it is an act of pure, self-obsessive logic)
But a suicide committed to escape from a life well-lived has no equal in terms of adventurous bravado.