Marriage Benefits in Reserves

My partner and I have been living together for three years with an undetermined marriage date. I guess technically she is my fiance, but there has been no hurry for either of us to get into a second marriage.

We have had some recent talk about the financial benefits we have been missing by not being married. I realized that I don't know shit about marriage benefits as a reserve soldier. I am doing some research on this, and posting to this forum for expert answers is part of it.