Dealing with non-Muslims

Q: I want to ask many people ask why we using non-Muslims' inventions practically and socially if we are against them?

Q: Why are we discouraged from taking the kuffaar as friends?

Q: I've been friends with a Christian girl for the past two years. She's always been here for me and so she became my favorite. After sometime, I came to realize that it's not allowed to be intimate with an infidel. What could I do, please?

Q: How should one treat a kafir if that person is your blood relation?

Q: Is it allowed to seek help/advise from non-Muslim when one is stuck in a problem. It is also possible that he will not help or give the advice.

Q: All Muslims say music is haram and give ahadith and quranic verse. I got a question from a non-Muslim who says that what is the scientific reason behind prohibition of music?

Q: Did Nabi (sallallahu alaihi wasallam) hate those kuffar (e.g. Abu Jahal) who were against Muslims?

Q: I was having a conversation with a non-Muslim acquaintance, and she was talking about her belief which had stuff to do with energy and spiritual stuff. And she was talking about things contrary to Islam but I did not clearly state 'you are wrong, I believe the complicit opposite, etc..." because she is very into being accepting and to me it seemed that telling her she was wrong and so on, right then and there, when she doesn't know much about Islam would turn her away from Islam and make her think is was a harsh religion.

Note that I am not apologetic about Islam in any way, I just did not want her to turn away from Islam before she understood what is was about. Is staying quiet like this a sin? Even though she knows that I am Muslim and do not share her beliefs, if I don't refute them out loud, is it sinful?

Also, occasionally I would shake my head or say yes when she was speaking, not as a way of agreeing with what she says but rather as a way to show I understood what she was saying. As I said, she knows I am Muslim and have different beliefs. Is this a sin? Would this take me outside of Islam?

I met with a second time, and once again I did not outright refute her when she talked about beliefs and I did not feel confident about giving her dawah as I feel I do not have enough knowledge to speak, and I am generally very inarticulate so instead I gave her a book on the introduction to Islam. Is this right?

Q: Is it permissible to give a non Muslim a tafsir of the Quran with ayat in Arabic?