Both should make extra efforts to be reliable, to do what you say you are going to do. The party abroad should be able to communicate clearly to his/her partner the difficulties s/he faces and not only talk of goodies and trappings abroad. Execute the proposed project without cheating. If you each know that you are trustworthy in little things, you'll be able to trust in big things. Trust that the other person's social life wouldn't be a threat to the relationship. Trust is so important that if it isn't strong, you can make a conscious effort to work on it, both on your own and together One big issue of living apart is missing out on lovemaking particularly the married couples. Try having phone sex together or erotic text messages huskily describing what you'd like to do to each other. This one is for married couples and yet to be married couples that are not religiously inclined. Be careful though.
Be a little bit balance. That's, independence but with a healthy level of dependence upon each other. When these are present, there is a balance of power in the relationship between both parties, and each person can be autonomous but still meet the other person's emotional needs. What this means is that with an appropriate balance of independence and dependence, each person is allowed, even encouraged, to grow and change as an individual, which everyone needs. It is, therefore, wise not to expect that your partner or yourself will always stay exactly the same as when the relationship started. The one abroad may have a cultural change and his/her way of communication may change. For example, here in USA, people use STEP. (Sorry, Thank you, Excuse me, and please). Such mannerism needs to be communicated to your partner so that s/he doesn't get you wrong when you talk. Let me add that the calls shouldn't be one party's burden.
If you think it is too dear to make a long call from Africa, do your best to call when your partner might not be at home and leave a short but sexy voice message. S/he would be happy to listen to it. One important thing one should take note is excessive demand. The party at home should be moderate in demand for money as much as the lifestyle. It is very important to know the strategies of coping up with long distance relationships. When you feel lonely, get involved in organizations or causes that you personally believe in. Help those who have challenging life circumstances. Make sure there are supportive people and places in your life. Every once in a while, do something that is atypical of you. For example, go to a movie on a weekend or get your haircut or hairdo. Tend to your spiritual needs by going to church (for Christians) mosque and other religious gathering. Here you should be careful of the charlatan pastors and prophets, else they would ruin your relationship
Specific strategies to try when the depression of missing hits you, especially a partner back at home. Let out the emotions: cry, scream, sing, exercise, go for a run, or take a walk. Write a letter to the person, whether you send it or not, letting her/him know how you are feeling. Write poems; watch a comedy movie to make you laugh. Make call or visit your in-laws or your would-be in-laws or read a book.
I believe couples can stay miles apart, and be able to maintain a solid, happy, successful relationship until they could be together again.