I have always been shy too. Having serious conversations about most anything makes me emotional, even after being married for 12 years! One thing that I have a hard time with is making eye contact during conversations - i just start to cry when things get tough - so I find it helpful sometimes to talk while we are driving in the car. If one of us is focusing on the road then somehow it seems easier for me to say stuff. Start small, with something that won't ruffle many feathers for either one of you. If you keep practicing it will eventually get easier.
One thing that helped me when I was much younger - right when I graduated from college - was getting a simple
Job at a local coffee shop. (Not a big chain, somewhere small with no pressure.) interacting with customers helped me break out of my shell a little bit. I had a reason to talk to them ("you look like you could use a cappuccino and a bear claw!") and it helped me get over some of my shyness!
Hugs,
Super Girl