You really should go talk to a lawyer. Usually they will do a free initial consultation, and you can get these questions answered as they apply in your state. A lot of states distinguish between short-term and long-term marriages, with a long-term marriage being one over 10 years. In those states, there might be little to no alimony for a short-term marriage, but lifetime alimony for a long-term marriage. So you have to know what your state does.
