I also have a hard time writing about men. What I do is imagine the same character but from a girl perspective with the same personality. It's not that I can't write about men I just don't enjoy it as much mentally. The personality can be the same but in my mind it's like meeehhh I prefer same thing but with a badass women. (Few exceptions here and there).
It is tough mentally. Why did I tell you this? Well, you can apply a similar concept to drawing. Instead of trying to add curves why not start small? For example, draw an androgynous character with a big jacket to cover said curves. Mentally imagine it is a small man with andorgynous traits but when you add the finishing touches make it a women.
Step by step start adding more feminine traits (like a small skinny man with long eyelashes and long hair). Going step by step while drawing something you are comfortable with will help you draw the opposite sex in a more natural way without being too much for your brain.
