I rather doubt my story applies very well, but maybe it will get the ball rolling and open the discussion.
I graduated from an Assemblies of God Bible college after 10 years of going off and on as I could afford it and felt drawn back to complete my B. A. It was hard because I knew God wanted me to train to help others with questions of faith, but just didn’t quite fit in. In our situation, all the women were expected to do one of three things: 1) marry a guy who was training to be a minister and so be his “helpmeet”, 2) train for the mission field, or 3) go the religious education route and become a teacher. I took the 3rd route because it seemed the “safest” at the time.
All through that time I felt I ought to be there, but not that I ought to end up doing what was expected of me. I couldn’t define it or describe it, but I knew it deep inside. After I graduated I just took a job in the city and lived there, not having any clear direction at all and feeling a bit lost/at loose ends.
In my case, I returned to the Episcopal Church, met my husband (a rather confused Catholic at the time) and settled down thinking I had simply not understood what God had wanted for me. Later my dh wanted to return to the Catholic Church and I began to explore Church teaching. To make a long story short, I was reconciled to the Church and have found my “niche” in apologetics. My training in the AoG college has prepared me quite nicely to help non-Catholics understand Church teaching because I’ve been there and know where they are coming from.
We cannot know just how God will use a calling to serve him. There are many vocations for lay people that are valuable and good. St. Frances de Sales said that to have yearned to serve God as a religious and not been able to shows a love for God, his Church, and the community that is laudable and proper. It means we are open to whatever God wants for us and how he might direct our lives, so he can use us in any way he pleases. So, if you don’t fit in the seminary or convent or whatever, just let God lead and all will be well no matter where/how you end up serving.