You are not married to the guy...so all the "marriage stuff" doesn't even come into play and you really don't even know the old or new Scott.
He is in prison for B&E, he is where he should be. Do you have any clue whatsoever what his future will look like after he gets released? A felony and prison on your record is serious business, it will affect his credit, his employment opportunities...his entire future and if you marry him, it will impact yours as well.
I would read Codependent No More and Women Who Love Too Much and google Adult Children Of Alcoholics/Drug Addicts...children are the true victims when they are raised in a home where addiction is present, not to mention some will be genetically predisposed to either becoming an addict themselves or marrying one.
Might be time to learn all you can about drug addiction and codependency...and consider your familys input, they are thinking with their heads, not their hearts.