When there is much projection, there is no relationship because there are two blind people who talk to each other seeing all sort of things and they do not know it.
I found couple of ways to find projections
-knowing yourself, eg. reading dreams , it seems to reduce projection, as then internal things can be separated from external things. The problem is with projection when one confuses internal things (qualities, traits, subpersonalities) with external people.
-improving objectivity, the more you know your reality, then projections will stand out.
-trying to explain problems with people assuming that one projects