It is difficult to discuss serious issues (like a marriage proposal) while not in person... I've been apart from my boyfriend for the past year out of a 4 year relationship, and I know the struggles very well - we've only seen each other for a few days 2 times - just like in your situation, it is a matter of completing degrees in different places.

When you start to horribly miss the person you love with all of your heart, you may get the tendency to overthink things (I've discovered this in myself). I'm not saying that you have overthought your issue in any way, however, it may be a good idea to continue the conversation only when you two are visiting each other. Any fighting over Skype or email, etc. turns out much more hurtful in the end as it gets prolonged more, in my opinion.

Adding to Bill3's good question above regarding how many times you two have visited, how has he acted during those times? In 5 months his 1 year work contract expires right, so will he return home or is there a possibility of an extension? If there is for an indefinite amount of time, are you in a position where you could relocate to where he now lives?