I mean how busy are these so called 'friends' that they go for 'long periods of time' without calling or checking in? If you like someone you'll always make time to phone, email and text rather then the odd comment or two on facebook. I would hold a grudge if I were you. No one is that busy. If you like someone you make time for them. Simple. These are types of friends that go into my yearly cull basket if you please. You know the ones you mentally delete. They get moved into the acquaintance category. The above applies to acquaintances not true friends. Don't get me wrong acquaintances have their place in your life too but let's not get the two confused shall me. Someone that can't be arsed to phone or only wants to see you when it suits them is not a true friend. And why is it normally around this time of year? The time when people are leading 'busy lives.' Why does everyone have to meet up before Christmas? You've had a whole sodding year to get together. Yes let me drop everything for you. I wouldn't mind but normally they suggest it (bit like The Ignorer) you give them some dates then they can't make the dates you suggested and it never happens in any event.
Even if you don't live in the same country and with time differences, if you really like someone and want to catch up, you need to do so on a regular basis. You see, if you are only phoning once in a blue moon, there isn't a cat in hells chance that if feels like you 'just spoke yesterday.' You have more than likely missed massive chunks of tittle tattle that us women need to report on a regular basis. If you talk only once a year you could even be forgiven for saying "oh yeah that, we got divorced a couple of months back, wasn't working out." Whereas your true friends would have heard about all the details leading up to this point. I miss talking to certain 'friends' that I haven't spoken to in a week. I will always make time for those folk.
So if you see this on facebook how about commenting and saying "oh you have shit friends too and they know who they are!"