“Even with those odds Lee could not afford the losses.”
Correct. The South could not maintain their rate of losses.
The North could maintain their rate of losses.
Lee needed a military, economic, or political “something” to change the trajectory.
That “something” did not happen resulting in the disaster at Appomattox.
Would one of those trajectories include Great Britain
recognizing the Confederate State of America as a nation
and providing military assistance including using the British navy to break the Union blockade?