Are You Even Listening To Me?

Ever been in the situation where you're waiting for the "right" time to speak and then when you've just started speaking, someone interrupts you and starts their own bloody conversation. 

Yeah, my life.

It can get tiring repeating everything you've just said because the other person wasn't listening. It doesn't make it seem worth it because they'll probably won't listen again. It can be awkward when you do say everything, and then no one actually replies or ignores you. Doesn't it just make you feel uninteresting?

Either that, someone has to interrupt my conversation, start a new topic and everyone else focuses on that instead. I feel like giving up. It's rude. 

I end up not talking most of the time and just listen.