So, I once played online with a stranger who had a Siren with a Legendary Nurse build and we were UNSTOPPABLE!
I’m also looking out for regular partners to play with, but this is my main goal.
What platform are you on? 
Ask a mod to move you to the appropriate platform section so that you can find someone- you may play as Krieg but when looking for partners to play with the platorn section of choice would be a better way to find it…