More and more platforms have been hacked and user data has been leaked as a consequence. Even large and reputed providers like Adobe and Dropbox were affected. Just recently another 500m user credentials have been leaked.
Hasso Plattner Institute, a very reputed German IT & tech research organization, has compiled a database where you can conveniently and securely check if your email address or any other user data has been compromised.
Anyways, you should consider using unique yet easy to remember passwords for every single service you use. This will save you hours of work and some sleepless nights, just in case 🙂