I am very busy with 5 kids of my own ranging from 4 - 20 years and always have 6 - 9 kids at my house. I have no time for myself let alone for someone who purposely moved over an hour away to put distance between her family and her siblings. I did my shopping at the last minute and instead of buying one expensive gift I purchased several inexpensive gifts and sent them with another relative, opting out of traveling for the day. When I saw the other relative later I was chided several times for purchasing more than one gift and not attending. I cant help being a realist. I have helped many kids get there first apartment and I know this kid was going to end up with a $100 coffee pot and no cup to drink it out of so why the big deal over multiple gifts and not attending?
As for the shower thing, I would just forget about it. I can maybe see how sending the gift with someone else as opposed to mailing it could send a slightly off message. Clearly you have kids and barely have time, but maybe they felt like you didn't feel it was important. To them it probably was important. Everyone sees these things differently. Also, if you were the one that's been asking for more inclusion, I guess I am not understanding why you aren't taking them up on things.
And not all family has to live 10 minutes from one another. It's perfectly normal that family members live within a few hours from one another. Jobs, schools, work, it's all a factor in where one lives.