Due to remembering past sexual trauma in college with a good deal of regularity, I had a spell of vaginismus. It's not easy, and it can be really frustrating and upsetting.
I found that what worked for me was simply having the patience to work with it and go very slowly when it came to any sexual activities. Dumping intercourse altogether for a few months -- and dumping the idea that I had to keep trying to make it work -- helped a lot. Sticking to manual and oral sex when it felt right, and gently, was what worked for me, and only when fairly rigourous manual sex felt good did I then start thinking about intercourse again.
Some folks find it's helpful to see a sex therapist who uses vaginal dilators slowly over time, though if the source is psychological, I'd highly suggest pairing that with good therapy. It's great that you have a partner there to support you who you can work through this with: it isn't a death sentence... vaginismus need not be a permanent condition.
Just take it slow. Very.
Editor and Founder, Scarleteen
My epitaph should read: "She worked herself into this ground."
-- Kay Bailey Hutchinson