If you'd have been raised a Mormon, a Mennonite, a Lutheran or a Muslim, you'd have thought your situation with your boyfriend and getting pregnant etc, was due to having left one those organizations. You were raised JW so that's the one you ran back to because it is safe and familiar.
Just because your life didn't turn out they way you wanted, doesn't mean that the JW's are the one and only truth in the world. Many a "prodigal" Mormon girl felt the same way you do, when she returned to the fold when things didn't turn out well after she left and many an inmate has expressed the same sentiments as you have, when they found Jesus while in prison. Most people are better off if they are following a set of rules or standards rather than bouncing from one thing to another and not really having a firm goal or vision in front of them.
If being a JW gives you a sense of belonging and something to lean on until you gain some maturity....then I say go for it. Just keep your eyes open...keep asking questions and be aware that in the past, you have been a bit idealistic about things and it lead you down a path you didn't want to be on. Make sure that this isn't what's happening now, so that you don't waste anymore time and have it end in disillusionment. Being a "moral person" and living a "good life" and having a "personal relationship" with God, shouldn't have to include possibly letting your child die because some organization decided to use connect the dot scriptures to erroneously show that blood transfusions are supposedly wrong.
To be brutally honest, a lot of the things you've said sound very cliche' and cult-ish. It sounds as if you're repeating the lingo that someone else came up with rather than ideas of your own. Be sure you thoroughly understand the beliefs (especially the blood issue) and are aware of the real reason you are going back to this organization.