O'day widgeon specs:
WIDGEON 12 (O'DAY) sailboat specifications and details on sailboatdata.com
Rhodes 19' specs:
RHODES 19 CB sailboat specifications and details on sailboatdata.com
If you compare the displacement (weight) of these 2 boats you'll see that they have very little in common. The Widgeon weighs < 200 pounds while the R19 weighs > 1000 pounds. The R19 is more like a tiny pocket cruiser than a dinghy.
It would take a lot of force to tip over a 1000 # boat but not a whole lot of force needed to tip a Widgeon. Another useful comparison is your body weight as a percentage of the boats displacement. On a Widgeon a 190 Lb. man's weight is 100% of the displacement; on a Rhodes 19 the same man is about 20% of the displacement, so your body weight on the Widgeon is extremely important for keeping the boat balanced but on the Rhodes not so much.
So, JoeLena, keep sailing your R19. The only thing you have to worry about is when the wind is strong enough your R19 can get knocked down. For strong wind you can either put a reef in the main sail or drop the jib and just sail with the main.