Timis, you need to chill.  There is quite a bit in your post that I believe you just need to "let go".

I think your sister needs to "chill" as well.

I'd like to say that your Mom needs to "chill".... but maybe that is not the right wording.  I think your Mom needs to accept reality as it is.  As hard as that will be for her.

Your brother made a choice. He made a decision whom he would marry. He made that decision. Now, he has to follow thru on that decision. His wife needs to be first - before you, before his siblings, before his parents.  Like it or not, that needs to be his priority. The choices they make where to travel, to vacation, etc .... those are their choices.  You don't get a say in that.  I'd learn how to "bite my tongue" on them. Etc.