Spacing IS the issue. You get "stuck" in a situation when you make mistakes. I am not saying players should be immune to making mistakes, but you cannot write that off as the games fault. If you are stuck in the corner with no stamina, you should be at a disadvantage. The player worked hard to put you there and force a break, I think they should be rewarded.
Refer to above. I will rarely have a perfect game of never being jumped on, but you can ask anyone I play that I make it as hard as possible to jump on me and punish as often as possible. Focus your game on the things you think are unfair instead of asking them to be changed, and you may not think they are as unfair.