Hi Lauren - I'm sorry to hear that you are feeling so down and scared about leaving your family and returning to BA. I am certain that I'll have the same feelings when I make a visit home later this year and I've been dreading it, too.
I don't know about you, but I constantly struggle with the two sides of my personality - the homebody part of me that wants to live close to my family and the adventurous part of me that wants to live in new places. I know that I can't entirely fulfill both parts at the same time, which means that I'm constantly making a choice between them.
For now, I've chosen to fulfill the adventurous side of me because it's much
easier to do it now than when I'm older. It sort of feels like the logical thing. I'm young, single, my parents are in good health and I'm at a place in my career where it's possible to pick up and live halfway around the world. The older I get, the harder will get, especially because my desire to "settle down" near family continues to grow each day. And this is an important experience that I want to have. If I don't do it to its fullest, when I "settle down," I will have regrets. I will feel like I missed out on an important life experience, on seeing the world. So, here I am, having that experience, and I'm not leaving yet because I'm still in the middle of it and I'd have regrets if I cut it short.
I'm not sure what brought you here, but I imagine you had your own justifications and reasons for coming here and staying, too. Reminding yourself about those might help. It might give you a purpose for returning. Perhaps write down those reasons that you came here, along with the goals you had for living in BA, and then write down how far you've gotten on each thing. Did you accomplish what you came here to do? Is there more that you could make a renewed effort to work on? This would define your purpose, which may help you feel better about staying here in the face of such a big sacrifice. (Because it IS a sacrifice.)
It's possible that going through that process (evaluating your reasons for living here) might bring you to the opposite conclusion, too, and you'll decide that it's time to go home. And that is OK! It sounds like you'd have a wonderful place to go back to. But I'd suggest that you not make that decision until after you've returned to BA and given yourself a few weeks to readjust. Right now, you're looking ahead to a big transition (leaving your family) and it seems really big and scary, but I'll tell you, the anticipation of the transition is usually worse than the real thing. Human beings are resilient and we have an amazing ability to make the best of what comes our way. If we're feeling bad, we make changes to our situation in order to feel better, and our brain adapts to it in ways that we don't even control. Things that we're forced to experience, which seem awful at first, start to not be so bad because our brain adapts on its own.
However, when we're anticipating something bad, we can't make changes to improve it because it hasn't happened yet! And so you're kind of stuck with that feeling of, "Oh boy. That is really going to SUCK."
So, the anticipation of something bad is usually worse than the thing itself for that reason, but also because humans are not the best predictors of how a series of events will make us feel. We tend to overestimate how good or bad something is going to make us feel. That's not to say that you won't feel shitty when you say goodbye at the airport, or when you walk back into your apartment here in BA. But that you will probably get through those sad feelings easier than you think you will. You have the ability to deal with them, and you will. And before you even know it, you'll be back into your BA routine living your BA life - still missing your family and having moments of loneliness and homesickness (I'd guess that most of us do), but overall feeling good about continuing your life here.
And if that doesn't happen, for some reason - if you're still feeling like shit after you've settled back into your routine for awhile, and your desire to be with your family has overcome the positive things about being in BA - then that probably means it really is time to go home. And so you can. It will always be there for you. You don't need to rush to make that decision right now, when you're right in the middle of all the emotions that being home can stir up. Agonizing over it for the rest of your visit home is not going to help you decide what to do. You need to wait until you're back in your regular life to assess your feelings and make your decision. Vacations are deceiving, because they feel so wonderful and great and we want them to last forever. But you and I both know that at some point, the honeymoon ends, and real life is there waiting for us. So, if you can, you should make your decision when you're in a "real life" state of mind, not when you're in the middle of a break from it.
So, I'd suggest you allow yourself to think through this a little more - maybe do that writing exercise I mentioned, read the advice we leave for you - and then set it aside to tackle once you're back here. After a few weeks being back, you'll have a much better understanding of whether you can handle living here anymore. And if you decide that you can't, that you're done and you want to be with your family, then you already know what you will do.
What I've written has gotten very long and I don't really have time to edit it, so it's sort of stream of thought, but I hope it can help, a little. I'll also share with you a couple of links that helped me a lot when I was hit by devastating homesickness last month. (A couple of questions that I asked about it.) It's a different situation, but there might be some pearls of wisdom that speak to you, too.
Best of luck with whatever you decide.