It's an inevitable part of human nature to become like those around us. It's easily noticeable for those who travel a lot; we tend to pick up on new accents and mannerisms without even realizing it. As humans we want to be accepted by other humans, so we subconsciously (or consciously) try to become more like them. This can be hilarious at times, such as when I catch myself imitating a Southern drawl with my dad's relatives in Texas.
This imitation becomes a problem when the other people are exhibiting behaviors or attitudes that are not healthy for us to emulate. Although most of us can keep ourselves “on track” despite a few distractions, we are still very susceptible to the example of those around us. This is why racism, sexism, homophobia, and other negative attitudes are still so rampant: The people who hold these views tend to create their own “social bubbles” where they mostly associate with people who make them feel justified in their current attitudes. Or, at the very least, people who will not call them out on it.
But if we want to grow, then we have to get out of our comfort zones. We must pay more attention to what influences are affecting us the most, and make changes when necessary.
If you want to be a better Dominant, surround yourself with mature, experienced Doms who will be a good influence on your abilities.
If you want to be a Submissive with healthy communication habits, surround yourself with experienced Submissives who have these traits.
If you want to be better at polyamory, seek out people who are successful at managing multiple partners and metamours. Spending time with them will rub off on your own poly groups.
If you want to grow in emotional maturity, surround yourself with people who are more mature than you are, and don't be too proud to let them lovingly point out areas that need improvement.
If you want to manage your mental health better, spend time with people who understand you and who will encourage you to develop healthy coping skills.
What often happens, though, is that we surround ourselves with people who are hindering our growth and then wonder why our lives are so chaotic and unhealthy. Instead of being influenced by people who will encourage us to better ourselves, many of us spend our time trying to win over people who do not really value us, or who don't care about bettering themselves. Instead of becoming better, we start to lose momentum in our own growth because our closest influences are telling us that it's ok to stop growing; it's ok to give in to our unhealthy habits and negative attitudes. This stifles our personal growth and makes it much harder to increase our own emotional maturity.
So how do we balance all this? Obviously no one is perfect, and limiting our circle of friends to those who are “good enough” is not exactly a healthy thought either.
I think what's important is that we are simply aware of how our closest influences are affecting us so we are not sacrificing our own growth or stability for their sake. I think it's not so much about cutting “bad people out” as “bringing good people in”. The more emotionally healthy, mature people we have in our lives, the better equipped we will be to help those who maybe can't be a good role model for us right now. These good influences can also help us recognize when we are being taken advantage of, when we're being an idiot and need to be reigned in a little, or when we are overreacting or lashing out. It's uncomfortable, but accountability from those we trust is important if we're going to become better friends, partners, lovers, Dominants, Submissives, etc.
By building a close inner circle of people that will help us grow into our best self, we can then help others grow too.