1. The thing is, it's neutral.
2. So what, I got through it some how.
3. Well, it's a little sadder.
4. So, if (he's) with someone else, then I'd start to worry. Because I was rejected because of someone else, and maybe not for long, It's such crap.

So, the 4th one is really confusing.  It seems like this is part of a conversation, so it might be a little different based on the context.  Anyway, I did what I could.  Hope it helps.