Dakota,
A few thoughts-
From your husband's machine, try sending yourself a message. What happens, does it bounce, do you receive a notice of undeliverable mail or what (if anything)?
In Mail, select your Inbox, then go to the menu bar/Mail and Rebuild the highlighted Inbox. This may take a few minutes. When this is done, restart in Safe Boot mode, and then restart normally.
Any alerts, notices, etc?
And just to be sure, check your Rules to ensure there is not a rule to trash mail from any recipient (or similar rule).