why didnt Rick just jump at Negan when Negan was up close?
in real life, what is the best option when you know you are about to be executed?
For starters, like gorcorps said, Negan's MO is to kill one person as an example, and then take half the groups stuff as tax on a regular basis. He doesn't need to kill everyone...just one person & then show up with 100 bad guys to show his strength in numbers. Nobody else we've ever come across since the show began has had a group as large as Negan's.
Second, there's more involved. For starters, Rick has a baby girl back at HQ to think about. Plus, Negan isn't going to kill Rick, because if he kills the leader, then the group that he wants a 50% tax from now has no one to lead them. He doesn't want to setup infrastructure; he wants to run it like a franchise & just collect income, based on fear. He killed a 17-year-old boy back at Gregory's camp with the Hilltop people, so they know that he not only has strength in numbers, but he's willing to follow through & use it as needed to keep them in line.
So if it's your turn to get whacked, you can either stand up & take it or wuss out & still have to take it. Your friends can try to rescue you, but they'll end up dead as well because there's literally 50+ bad guys around you & you have no weapons, so it's a sacrifice. The writers set it up pretty well to not have any wiggle room out of the situation, and everyone else realized that they either have to sacrifice one of their own, or risk losing even more, because there were literally no other options at the time.