What makes you think the girl that you are paying her school fee will later get married to you, women can not be trusted since ancient times, what makes you believe that your girlfriend that you have been paying her school fees today will not get to marry another man and tell you that you have tried and God will bless you for the help you have render since when she was in school and now she can't continue with the relationship that her heart belong to some one else that she is sorry for what ever pain and sadness she might have cost you that she is very sorry and she apologized sincerely.
Let me take you back a little on why you don't need to invest more on a woman that is not your wife , God created Adam and told Adam not to ever eat from the forbidden fruit, and Adam obeyed, he never for one day go near the forbidden fruit not to talk about even getting tempted by the serpent snake, now eve was created and he told eve that he shouldn't go near the forbidden fruit that God instructed us never to go there, she agreed but surprise by Adam that she broke the deal and eat the forbidden fruit.
If a woman can do this want make you thing she cannot break your heart even upon every thing you have done for her since you get her as your girlfriend
Today it is normal for men to see a lady approach her give her your words and she agree to be your girlfriend, then you start spending on her till the extend you decided to invest in her education thinking that you will get married to her but unfortunately for you she turn down the deal which was suppose to be "after I finish my education we will get married" and then she came back from the university and told you that she can't continue with the relationship anymore .
At that point you the man knows that you have lost it all, all your investment, the years you spent waiting for her to get through her school and get married to you, the money you spent for her in school (school fee, handout, pocket money, cloth, hair etc) then you realise that it all gone and another man will ripe off what you sow for long.
This is just an advice to men not to invest heavily on his girlfriend Rather channel that investment and energy to your wife and you will enjoy what you sow.
Some men just love to spend outside than to spend for their wives, it sounds very funny