Military regulations chiefly regulate against dating between two soldiers of different ranks. The U.S. Army, Navy, Air Force and Marines all have regulations in place prohibiting this activity as a kind of fraternization.
Can you date other military members?
Typically, it applies to unprofessional relationships between officers and enlisted personnel, but it can extend beyond rank too. Fraternization can apply to close friendships, business relationships, or even certain financial exchanges between Military Service Members of different ranks, regardless of gender.
You do not have to wear your uniform when off duty, unless you are in certain training environments. You should not wear your uniform when you are off duty, except for transportation home. Some military assignments have strict rules against wearing a uniform while off duty, especially when stationed overseas.