Hi Anjel
Welcome and thanks for sharing your story with us.
For me Paul's letters to Corinth are more difficult to understand than his others, because he was responding to specific questions or arguments from the Christians there, and we do not have those letters that the Corinthian church wrote to him. Of course there is plenty of theological material in them too, but there are several things that make you ask "Why is that in there?" Ray said he really had no idea what was going on with the "women must be silent" controversy, because that pretty clearly "contradicts" other scriptures where women prophesy and speak truth. Something was going on in the church of Corinth but unfortunately we don't know what. (But that's where faith comes in....we don't know all the answers. Eventually we will understand how it all fits together.) My point in saying this is we don't necessarily have to apply all of Paul's words literally to our own 21st century situations. In the case of the passage you quoted, we do have some extra information provided by Paul later in his letter. In 2 Cor. 11:13-15 he writes there were people pretending to be Christians but who were actually ministers of Satan. THAT is the group Paul admonished the church to be separate from.
As for your own situation, I advise you not to feel guilty about hanging out with others who are not like-minded. I think it's fine to socialize with people who have common non-biblical interests, such as rap or anime. Of course, discernment is required. I don't have to tell you about the dangerous influence of certain hip hoppers, and if you have anime buddies who want you to get drunk and watch porn....find some new anime buddies.
I also advise you to not be afraid of hanging out with Christians. Because Ray was so hard in his letters to Hagee and Kennedy (and rightly so), a lot of people on the forum made the mistake of generalizing, thinking all Christians in church were of the same mindset, that they all like the idea of hell, don't know anything about the Bible, etc. A lot of the posts from this forum's early days don't look good in hindsight; there are posts oozing with arrogance, laughing and mocking the church for being so blind and stupid, and how can they actually believe this or that? I shared in that attitude myself. Because of my anti-church attitude, I didn't see much spiritual growth in my life for several years after learning the truth of universal salvation. I foolishly thought I had reached the mountain top, so to speak (because what knowledge could be better than universal salvation?). I shunned Christian music and books or activities associated with "non-universal salvation" Christians. I was a huge fan of certain metal bands and most of my friendships were with non-believer metal fans. This was a big mistake on my part. Not that my friends were bad influences (our activities were all family friendly); but my anti church attitude left a sort of spiritual void in my life, because I threw the baby out with the bath, as the saying goes. My life is much more enriched since I've changed this attitude. Almost all the music I listen to is praise/hymn music, and I read books and listen to podcasts by believers who are in church, and yes, believe in eternal punishment. There is a lot of excellent material in some of the apologetics books I've read. It's far more beneficial to read an apologetics book--and skip the chapter on hell--than to throw it in the garbage and headbang to metal. I'd rather hang out with a hell-believing Christian and talk about the Bible than talk about sports with an unbeliever. (And I'm a big sports fan.) Despite what many of us on the forum initially thought (and some probably still think), there is a lot of common ground with us and the hell believer. I can discuss our shared beliefs, and introduce the person to universal salvation. If they don't accept it at first, fine. That doesn't mean I have to give up and insist on hanging out only with non-Christians. Christians are more on our side than NOT on our side. (I speak generally. Obviously there are some purposely wicked and deceitful people in the church.) This has become more apparent in the last few years. While the world is ready and willing to accept anything, certain Christian leaders--yes, even some who believe in hell--are standing their ground, insisting that homosexuality is a sin, and there are only two genders.