sinking....

So, what do I do now? I made what I feel like was my last attempt to touch base with someone who used to be one of my best and closest friends... Life has taken us both in different directions, down different paths and to different parts of the country. The separation began towards the end of college, and progressively thinned and stretched until now. I don't want to lose her friendship, but I feel like I already have. Most recently, I sent a message via Facebook to check up on her, see how life was treating her, how her recent trip to South Carolina (which I learned of only from Facebook-stalking) was, etc. It's been probably 4-5 days and I've heard nothing back...yet she's had time to update her photos and post multiple status updates. So my message was obviously ignored...and more than likely deleted. Now since my fiance and I got engaged, I've been constantly going back and forth between whether I invite this person who I haven't physically spoken to in over a year, haven't seen in over two years and haven't heard a peep from otherwise in months.... If I did invite her, would she even come? It's frustrating being the only one trying to keep a relationship above water.