Why did it affect our lives so much??
Because the elder system acts much like parental authority, ie, that you MUST tell them everything and that they have CONTROL over your life, what you should do for a living, whom you "should" marry (or experience being looked down upon), what you should wear, who your friends should be, whom you should associate with, what your entertainment should or shouldn't be. They can shun you or shun a family member for not agreeing totally with them, they can shun you for a "bad attitude" (as well as serious sins if they deem you are unrepentant) and if one doesn't go along with the shunning process, then they risk being shunned as well.
Notice I used the word "should" .... they use words of these type to by-pass the word "must".... this way, they can say the choices are really up to you! In this way, they decide who is and who isn't "spiritual" and one must only associate with "spiritual" people or risk being dragged down.
Many of us have lost relationships with family members when we became witnesses. Many lost relationships with friends and family when they left or got disfellowshipped. So why are we so passionate about this? Because family and life-long friends will not speak to us or risk being cut-off. Because many people gave up college educations to do what was considered "spiritually correct" in order for them to purse ministry work and low paying jobs; because many people gave up good jobs with retirement benefits to take on part-time work in order to perform more work in the ministry; because many people DIED because they would not take a blood transfusion, etc.