This is a fairly comprehensive review of the variety of approaches you can use to model recurrent events in a time-to-event model. The authors share some code as well. You might need to review some of the references to get a more complete picture of some of these approaches.
Leila DAF Amorim, Jianwen Cai. Modelling recurrent events: a tutorial for analysis in epidemiology. International Journal of Epidemiology, Volume 44, Issue 1, February 2015, Pages 324–333. Available in html format.