I've been called a lot of thing but never a lady!
Lot more guy's around here then women as this is still "a man's job". 51 isn't to old for this but with that in mind you might not even consider flatbeds or even some tank jobs cause the heavy hoses. I recommend hooking up with a good dry van company that does not expect drivers to load/unload, that way you can concentrate on safe driving and not so much worrying about reefer temps or straps and chains ect. After awhile if you want to get into that kinda thing then you got the driving down pat.
Just a quick FYI about getting along out here, lots of guys will be looking at you if you dress and act like a professional driver most will treat like one on the other hand if you dress and act flirty they'll treat you like a lot lizard.
Hope you do well and good luck.