Time and time again we hear people say why cant I find a good man/woman? Or Why do they always do same thing? The answer may not be what you think. 
We often look in wrong direction when seeking these answers? Now I will not say its always one way or the other but we seldom (if ever) look at ourselves when seeking these answers. Ok many times those we chose for a relationship were not a good match and maybe not even a good person. However when we complain that we NEVER find a good one or that they always do same thing we need to look in the mirror very likely. So lets look at both questions but from a different viewpoint.
Why cant I find a good man/woman?
If you cant find a good partner and this is a constant it may be in the way you look/choose. I say this because it is happening over and over again. Where they may not be a “good” match for you it may not be all their fault. You “chose” to date them! If this happens a lot it could be in “your” selection process. Before you blame those you dated look at process you use to find romantic partners and change it. Clearly what your doing is NOT working. Except some of the blame and you stand a much better chance at a long term relationship.
Why does he/she always do this?
This is different than the above as it may have NOTHING to do with your selection process. If all your EXs are doing same thing (controlling as example) you have to ask why? But by asking why we or you need to look in a different direction again. If your partners keep doing same thing and your already aware of this and not happy how is it happening? There’s a good chance its something your doing that brings out this negative behavior. Now the negative behavior may well be wrong and person doing this wrong as well yo have to see what your role in this was. Its very unlikely every person you dated was a “control freak” (as example) yet they got that way. There is a reasonable chance you played a role in this. So again look at yourself see where you contributed to this negative behaviors and look for ways to stop it.
Bottom line we cant change people but we can change ourselves and they way we react to them. If all or most of our relationships end in same way the common denominator is us! The good news is we cba change us!