Home sickness will happen especially if you don't speak Ethiopian. So before you come to Ethiopia, try to learn at least some basic Amharic. Also, having sex with Ethiopians will make you feel much more connected (and probably not wanting to go "home" anymore).
In places like Addis and Gondar, you can find other foreigners. So you can make some foreign friends. Also the °µÍø½ûÇø community may organize trips or parties. So when you get a house, make sure that there are other °µÍø½ûÇøs in your neighborhood.