Hi Activelife,
Welcome to the forums!
For your first question, unfortunately that's something only you can answer. There are all kinds of definitions out there you could look at, but there isn't a one size fits all. I used to look at loads of definitions until I found one that didn't fit my drinking. You know, "great, I'm not an alcoholic because I don't..." while ignoring all the boxes I was ticking. And also some people will drink until their world collapses, and then seek help. Others see which way they're headed and decide to get off the train before it goes off the rails completely. We're all different, and what one person might consider moderate drinking could have a hugely damaging impact on someone else.
For your second question, it's a big step to quit, and it's true that it can have an impact on relationships with friends/family, usually if they have problems with alcohol themselves. But the advice you'll see on here over and over again, is that when it comes to sobriety, you have to put yourself first. It's your life, and that's all you have control over. Don't keep drinking to make someone else happy if you're at all concerned about what it's doing to you. My wife still drinks (she's not a problem drinker) and while she was thrown by my decision and grumbled about having to drink alone now, I'm so much happier sober, enjoying life so much more, that I'd say our relationship has improved, not suffered.
Whatever you decide to do, you've definitely found the right place for advice and support. If you want to quit, every possible method for doing that is discussed here and there'll be loads of people ready and willing to answer any questions you have.