If I were much younger, I might have said directly to my friends, "Eh, tak ajak aku pun!" which means, "Why didn't you invite me out too?" whenever I know some friends hang out together without me.
However, I don't think it bothers me as much now.
I have passed the stage where making friends is the key to life. Right now, I am more keen to keep the ones whom I treasure the most and only the ones who still bother to keep in touch with me regularly.
I know it is not easy to read one's mind, but it is not hard to tell how important (or not important) you are to some people.
If you are always left out from some events, you should get the idea that you are not in their VIP list anymore.
If people keep on having the same excuse of forgetting to reply to your email/whatsapp/messages, it also indirectly means you are definitely not in the top priority of their life.
If you are the only person who keeps on insisting to meet up but the other person always forgets to get back to you, it probably means you are the only one who is serious to keep in touch. So, just forget it.
If you get messages from your friends telling you how much they miss you, and you cooperatively trying to keep in touch with them again but in the end they are nowhere to be found, it implies that they were just saying some sweet nothing and were not really sincere in saying the ‘miss’ word. So, get a grip!
People can justify by saying that they are really seriously undoubtedly very very busy with work and of course, with their family. When that happens, nothing else you can do besides saying how much you understand.
Well, what other things do you think you should say? It’s not about being hypocrite by not telling your true feelings, but being mature is the best thing you could do to save the relationship.
I also realise that showing how much you care does not seem to be the best thing anymore. You might sound like a busybody rather than a caring person. Getting older also means having more responsibility and more problems. Since you might not want to create extra problem to your friends, staying away from them once in a while would be the key.
Because one day, you might need your own space too.