OMG! First! YOU ARE NOT STUCK!! You have control of your own life! This man is possesive and controlling to say the least! It is time to move on and get away from him. I fear for you at this point, now is better then later. His behavior will most likely get worse and never get better.
I understand you have been through some tough times, it is never easy to lose a parent, but this may be a time you need to experience so you can become stronger and find out what it is you really want, need and desire in both a good (key word here) man and life.
Take it by the horns, send him back home, do not marry him and seek out some support for what you are going through.
Go back to college, get your own life back, do not let him take it over for you.
The fact you are ready to take your own life shows you are not happy with him or you would not be unhappy enough to consider this.
Please, be strong, send him home, start involving yourself with activities and other people and take your life back so you can find your happiness again. I know you can do this, good luck and big warm hugs to you.