i had a really close friend who grew up in a really dysfunctional family. her mom has untreated mental illness and her dad is alcoholic. she is a really good person, but really struggles with healthy communication and intimate relationships. we lived together for something like 6 years. i learned over that period of time that while she didn't "mean" to be so negative, it was her "default" setting in close relationships to be passive-aggressive, talk behind my back, and not be honest to me about what was really happening with her. she did a ton of "splitting." meaning she went to people we were both friends with and lied to them about me... or just twisted something that did happen or that i said and make it into something really horrible. basically she went to people and told them what a terrible abusive person i was. she even suggested (behind my back) i was abusing my son by taking him to OT for his sensory disorder (because the *real* problem was *me* not his SPD). very crazy behavior for someone who said she loved my son and i. needless to say, it destroyed our relationship.
anyway, the point here is, i think we all learn *how* to communicate at home as kids and if we learned an unhealthy or dysfunctional style of communicating, we need to work really hard to change that. i have found NVC to be the biggest help for changing my actual communication style. i have also found compassion meditation to help me most with getting past being angry at people. and i have found "the work" by byron katie to be the most help in accepting people as they are.
good for you for knowing that you want to change. the biggest stumbling block to our own growth as a person is blaming others for our feelings and behavior. good luck!