body weight and ground defense

Okay, so I know that ground work is not so much about weight as it is about technique, but honestly, it plays a major factor in a grapeling match. I'm a woman and slimly built, I only weight about 105, but am 5.10. What am I possibly going to do against a 180-225 lb. man? Is it even considered a fight from that point, cause' from my view it looks a lot like annialation. As I said, I'm small and not very strong, it is extreamly hard for me to put on muscle and retain it. I've been involved in Isshinryu karate for 6 years now and think that I have done exceptionally well for a student of that long. Maybe I was never taught the ground techniques that I should know for self-defense, but I want to know if I would even have a chance if I were trained correctly......

Please advise,

Go to the grappling, health/nutrition, and strengthening forums. Read, learn, ask, and apply.

Lather, rinse, repeat.

Yes, if you find a good instructor and train hard.