Personal or not???????

I'm quite an amiable fellow. Mostly agreeable to people and a ,firm believer in and of good friendships.

As expected I've gotten burnt a couple of times and while i do try, i cannot authoritatively say I've been 100% to all my friends. Surely i too have some shortcomings. 

However i do find myself wondering at some occurrences that seem to repeat themselves around me all in the name of this friendship. 

I hope this my intro is apt sef. 

A really good pal of mine has a habit of never mentioning her trips to me. I find it absurd. Especially when we could have been chatting up to an hour before the said trip(s). It makes me wonder, do people really prefer such information to be private? Are my expectations unreasonable? 

My sister's husband did it a couple of times and my dear sister said "oh well, they prefer their family issues private". The 1st time it happened they came to ask my mum to baby sit because my sister was away, next thing hubby too carries bag that he 'suddenly' has to go to SA. And i'm like why all the secrecy?. They even had the nerve to tell my mum that he only just got a visa, like he got the thing in the morning and wanted to travel that same night.... mcheeewwww. His second trip he called to say goodbye from the airport. Another trip he didn't even mention but returned with T-shirts for family members. 

My brother says he's allowed to do that, he is after all not a direct relative in the true sense of it. 

Back to my friend. 

She was relocating to another town and she only just told me after it had been done. I felt bad. Months after when i took her up on it, she said all the circumstances surrounding the move were embarrassing and it was a difficult time for her so she didn't/couldn't share. i disagreed. At the time i knew she wanted to take a trip and was even involved in sourcing funds!!!! then she got some cash moved and didn't even have the decency to bring it up! i thought she was coming for a holiday and didn't realize it was a relocation!!!!

Again it has happened. She was out of town for a bit, and we were in touch throughout. Even up until yesterday evening. Imagine my shock when a mutual friend just rang me to say oh did i know she was back in town this morning?

Called another random friend of mine, who said i'd buzz you later, i'm boarding a plane to the UK. Even though i felt quite slighted i still haven't discussed it till date. 

I'm quite annoyed and wondering what all the secrecy in this type of info is. Am i being too nosy here?