Family and life

Today, I would like to talk about my family and life.
About a year ago, my grandfather passed away due to cancer. ['due to' is usually how we talk about cause of death] And Just a couple months before that, I came back from New Zealand just because of him. ['a couple months ago' would mean November or December 2014. also, using 'just' twice is odd] He was my biggest reason to return from New Zealand and start my university life in Japan. He made me realize how much my family means to me and reminded me what I should care about most. [Keep the subject "I", since that's the subject at the beginning of the sentence.] At that time, I did not know that he had cancer. ['at this moment' means right now] For that reason, returning to Japan and seeing his last moment was like a feeling of following a path which had been already decided. [decided in the past, right?] I wish he could have seen my entrance ceremony. And now, even my mother has a serious sickness. [because you used the word 'now', keep your verb in the present for a more natural sound.]
Do you really care about your family? I respect that we all have different cultural backgrounds and customs, but it’s little bit sad for me to see my friends treating family with disrespect. [or 'disrespectful attitudes']
This might be a heavy theme for you, but this is my title for 2014, Family and Life.