Every now and then I am finding myself doing a solo Saturday ride due to training buddies being away, not available or purely because I personally feel the need to ride solo. It used to bother me riding alone. I know it's not particularly safe and whilst I now have more confidence on the road I never take my safety for granted. It doesn't matter male or female..I think anything could happen if you are in the wrong place at the wrong time.
Having said this I still look forward to riding long on my own. It cleanses my soul, gives me time to sort out any 'dirty laundry' in my head and also builds mental and physical confidence. There is no one to pace with, no one to draft from it's just you and the road...very much like a race day but probably a bit harder as you are not fresh and don't have any race day buzz to give you extra oomph.
I am not going to do all my Saturday rides solo (I hope not) but I am no longer scared of them...on the contrary I enjoy them and learn that 4hours in a saddle on a Saturday morning on your own really isn't that bad...I have some amazing conversations with myself, no one answers back and no one interrupts me and I am always right!!! Its great :)