When I try and go through nether portal, either return or not, I get stuck on building terrain, save quiting or force quiting both have the same result of sending me through to the other dimension but with the coordinates I had prior to going through, eg. Nether coords of 100, 50, 100 send me to overworld 100, 50, 100 and not to my portal.

Attached image was taken after minutes of waiting, nether sound effects were playing, only way to escape screen is X'ing out or alt+f4.