ATP can be hydrolyzed in two ways: the removal of terminal phosphate to form adenosine diphosphate (ADP) and inorganic phosphate, or the removal of a terminal diphosphate to yield adenosine monophosphate (AMP) and pyrophosphate.
Driving with failing or broken struts is dangerous because they do not sufficiently dampen side-to-side and front-to-back weight transfers.
To me it's prudent to replace both struts at the same time so that they wear at the same rate, but thats me..especially given your car is 7 model years old and especially if you have over 50,000 miles on them.