Yes, feeling uncomfortable when your girlfriend talks to her ex is a common emotion that can arise in relationships.
no, Because your the boyfriend and he is an ex only.
Tell him firmly to stop texting you, and ignore him if he continues. Be polite when he talks to you but have lots of excuses ready to cut the conversation short.
to get you jealous or his current girlfriend jealous or after to make you his rebound dont fall for it RUNNNNN!!!!!
Kill the ex bf
It doesn't necessarily "mean" anything, it's just something that happens. See the related link.
Why bother - there are plenty more fish in the sea .
because you miss her a LOT !
it means that you have a lot of admirers gal!
if he talks about her and or doesnt act himself around you
Take it one day at a time and move on.
It means they still like you.