Desperate Battler (Combat)Source Inner Sea World Guide pg. 286 (Amazon), Pathfinder Campaign Setting pg. 130 (Amazon)
Your experiences fighting against numerous foes that have already overwhelmed your allies, friends, and family have forced you to excel at fighting on your own.
Benefit: When no ally is within 10 feet of you and you are not receiving benefits from the aid another action, you gain a +1 morale bonus on melee attack and damage rolls.Source Weapon Master's Handbook pg. 24 (Amazon)
You can spend 2 stamina points to gain the benefits of Desperate Battler even while an ally is within 10 feet of you (but not when receiving the benefits of the aid another action).