Fudge didn't set after doing it twice
Soft caramel fudge sounds totally edible to me. Enjoy it and try again another time. When you do, test the thermometer in boiling water to make sure that it's still accurate. And, double check the fudge using the "soft ball" test. Set up a juice glass of ice water. Dip your spoon in the heated chocolate, let a drop fall into the ice water and examine it. If the chocolate has reached "soft ball stage", the drop of chocolate will be sitting at the bottom like a little chocolate ball. If the chocolate has a teardrop shape, or seems "loose", then the chocolate is not hot enough yet. 
Don't give up. Fudge can be finicky. Something as simple as the wrong pan can make things go awry. (note: My Father always used a heavy thick pan, like a porcelain coated cast iron, when he made fudge.)