Well even if that were the case,
But if it was the case, that means the star positions relative to each other would change depending on movement on the galaxy scale and thus you can't "know" if a star is supposed to be seen during an eclipse or not.
Again, stars stay where they are relative to each other, this is how we have constellations, this is how we find costellations. Therefore you can figure out where a star should be based on other stars.
As for how gravity affects light, kramer explained it very nicely.
You are assuming that they stay relative to each other. This cannot be the case because of galaxy movement in RET. The light would be affected by different stars so while they might literally be relative to each other, their observed locations in the sky on Earth would not be relative because their light would be affected and paths altered by different stars.
Look at kramer's post for the bending of light. Like i said, the light has to pass right next to a star or be behind it, so unless that is the case the light will not get bent a significant amount. And constellations do stay relative to each other in our sky.
How can you prove the constellations stay relative? Those stars are also subject to alteration of paths if only very slightly. Also, if the light is only bent very slightly, then there's a pretty good chance it will be bent many times considering there are a hypothesized billions of stars in the galaxy
That depends on how close the light travels to other stars. If the light travels at say the distance mercury is from the sun it will be bent a matter of inches, probably more like fractions of an inch. If the light is behind the star it will be bent a huge amount.
Oh, and you're right, major stars don't stay relative to each other, that's the reason why polaris moves, and the big dipper and little dipper will occasionally move so they're on opposite sides of the sky, and all the other constellations will move around.

The movement of stars so they aren't relative to each other takes thousands if not millions of years. Sure the north star may not point north, but it won't happen any time soon, we will all be long long dead by the time that happens, humans may not even exist by then.