I really don't think you are going to like my response - and really I should know better than get pulled into this, but hey, what the heck.
Two wrongs never make a right.
Trash talk is immature. No doubt about it. No one likes it, especially when it's aimed at them.
Not shaking hands with the entire team after a close game simple to get even with a few immature players in the dug out was probably not the most mature decision on your part.
The thing is - I think you know that now.
That said, don't you think it's about time to forgive yourself and get past it.
It sounds like the trash talkers are no more mature than they were two years ago. The question is - are you?