No-win scenarios, relationship friction, failures and mistakes, moral dilemmas and temptations, increased pressure and ticking clocks

The character limiting their intake of basic needs so loved ones can have them
Sending someone to near-certain death so they can find help in the aftermath of a disaster or accident
Leaving someone behind to act as a rear guard so the rest of the group can escape
Sending someone into a dangerous situation so people can be rescued
Assigning someone to sample a community's food supply that's suspected of being poisoned
The character choosing to be a whistleblower, knowing it will put a target on their back
Giving up one's life to save others 
Participating in clinical trials or an experimental medical treatment 
Firing a high-paid employee to keep others on payroll
Medical resources in an apocalyptic situation being reserved for those who are most likely to survive
Sending a spy into enemy territory to gain much-needed information 
Assassinating a despot to save millions of lives
Culling a sick animal from the herd to keep the others from falling ill

Having to choose who will be sacrificed 
Being criticized for selectively choosing the sacrificial person so it's not one of the character's friends or loved ones
Having to listen to biased, hysterical, or otherwise unhelpful advice
Having to explain one's decision to others
Having to persuade others that this is for the best
Being viewed as heartless for one's decision
Being replaced as the leader in the wake of one's decision
Being pressured by powerful people to do what they want

Failing to make the right choice
Being unable to live with the outcome 
Developing PTSD
Facing criminal charges for the decision
The sacrifice being unsuccessful or ineffective
The person risking themselves suffering serious injury or death
Having to watch the person suffer and carry the burden of their sacrifice
Having to interact with the person's left-behind family members
Watching the person die
Missing an alternative solution that would have made the sacrifice unnecessary
Being hated by others for one's decision, even though there was no good choice
Facing a mutiny in one's group
Becoming hardened in the aftermath to the point of apathy

ANGER, ANGUISH, ANXIETY, DEFIANCE, DEPRESSED, DESPAIR, DETERMINATION, DEVASTATION, DISGUST, DOUBT, DREAD, FEAR, GRIEF, GUILT, HOPEFULNESS, HORROR, INADEQUACY, LONELINESS, PANIC, POWERLESSNESS, RAGE, REMORSE, SELF-LOATHING, SHAME, TORMENTED

Second-guessing one's ability to choose the right person to act as sacrifice
Vacillating between various options
Being tempted to pass the responsibility to someone else
Finding the courage to sacrifice oneself
Relying on bias to make the decision (choosing a competitor or enemy, for instance) and struggling with guilt for not being more objective
Reliving painful moments from the situation (the conversation informing the person they would be left behind, the last glimpse of the person, the moment of their death, etc.)
Being overwhelmed by shame and self-loathing for not finding a way to save everyone
Knowing the decision was systematic and objective but still experiencing turmoil over it

The one who is being sacrificed, that person's allies, people close to that person, loved ones or friends who disagree with the character's decision

APATHETIC, CATTY, CONTROLLING, COWARDLY, CRUEL, GULLIBLE, IGNORANT, IMPULSIVE, MANIPULATIVE, MORBID, PREJUDICED,  SELFISH, STUBBORN, SUBSERVIENT, TACTLESS, VINDICTIVE, WEAK-WILLED, WORRYWART

Esteem and Recognition: The character's self-esteem or reputation may be permanently damaged as a result of having to make such an impossible decision.
Love and Belonging: A character who is unable to forgive himself or move past the decision may push people away and isolate himself, either as a form of punishment or to keep from getting close to people he will maybe one day have to sacrifice.
Safety and Security: In a situation where the group is critical to survival, any decision that puts the character at risk with that group will inherently threaten both his safety and security.
Physiological Needs: In a volatile, post-apocalyptic scenario where people are desperate and willing to do anything to survive, the character may encounter lethal resistance by the chosen one's family and friends.

A PHYSICAL ASSAULT, BATTLING A MENTAL CONDITION, BEING BULLIED, BEING DISOWNED OR SHUNNED, BEING REJECTED BY ONE'S PEERS, BEING UNFAIRLY BLAMED FOR SOMEONE'S DEATH, CAVING TO PEER PRESSURE, CHOOSING TO NOT BE INVOLVED IN A CHILD'S LIFE, CRACKING UNDER PRESSURE, CROSSING MORAL LINES TO SURVIVE, FAILING TO DO THE RIGHT THING, FAILING TO SAVE SOMEONE'S LIFE, HAVING TO KILL TO SURVIVE, MISPLACED LOYALTY, WATCHING SOMEONE DIE

ANALYTICAL, BOLD, CALM, CENTERED, CONFIDENT, COURAGEOUS, DECISIVE, DIPLOMATIC, INDEPENDENT, JUST, METICULOUS, OBJECTIVE, OPTIMISTIC, PERSUASIVE, SENSIBLE, WISE

Being able to save the lives of many people
Obtaining help or securing safety for a group
Being rewarded instead of damned for doing well in an impossible situation
The character finding forgiveness though they didn't expect it
Finding worthiness in being responsible for these decisions so others aren't burdened with them