HI Launa! Thank you so much for this post: https://success.salesforce.com/answers?id=90630000000gt3sAAA

I used the code in our org but got this feedback from a developer: 

"...since a trigger can process many opps at once, what could happen here is that isPrimary would be set to true if even a single Opp is primary, but what about the other opps potentially being processed? Similarly, iCount will be a total count of OpportunityContactRoles for *all* opportunities, not just one. So while this may appear to work when you change one opp at a time, it likely will not work - and in fact give the wrong info - when a bulk update happens on more than one opportunity." 

Any thoughts or advice here? Thanks for your time and help.

Best, Brooks