Dear Frank,  

The fact that you are having misgivings about marrying may either point to a weakness you have by which you find making decisions difficult, and in that case it would have been the same weakness that was behind your leaving the seminary twice. Or it could be a real struggle of conscience, letting you see that the reasons you left the seminary may not have been sufficient, or that you may not have embraced your vocation firmly while you were there. To get an answer to this ask yourself: was your spiritual director in agreement with your leaving, or did you make the decision either against his opinion or without asking for it? What moved you to leave? Did you at the time have any intention of returning?  

At this crossroads you have to ask yourself what does God really want of you? If you are to return to the seminary it will have to be a firm decision, and you may need some extra time in the seminary before ordination to make sure your decision is really firm. And if you really think that you should not, or cannot make a decision like that, you should put all thoughts of the priesthood out of your mind. The question then will be if this is the girl you should marry or not.  

If you are honest, God will bless you.