Karin,
My deepest sympathies.
Ireland is among the best places to go regenerate the soul. I visited the country in 1993 and have returned four more times. Friends and acquaintances assume I'm Irish because I keep going to Ireland, but I'm not. Ireland has always soothed my soul.
Make sure to see the green. I would recommend you see the Dingle, Kerry or both peninsulas off the southwest coast. I hope Rick's tour visits at least one of them. If the tour goes to those peninsulas and you have some free time, I strongly recommend a hike along the Dingle Way (http://www.dingleway.com/) or Kerry Way (http://www.kerryway.com/). Also, my guess is you'll go near Westport in the northwest. If you're feeling adventurous, climb Croagh Patrick (http://www.croagh-patrick.com/), the holy mountain of Ireland. It takes only 2.5 hours or so.
Either Dingle or Kerry is a great place to rent a bicycle. The Aran Islands along the west coast are also great for bicycle riding.
You might not have time for this since you'll be on a tour, but a decade ago my sister and I went on a religious retreat in Glendalough, a famous monastic site for more than 1,000 years. It's in the hills 30 miles or so south of Dublin. Glendalough is no longer a monastic site, but retreats are held there: http://www.glendaloughhermitage.ie/hermitage/. If you can't make the retreat, it's still worth seeing the monastic ruins. I'm sure Rick's tour goes there.
Everyone raves about the Rock of Cashel, a famous antiquity. It's definitely worth seeing: http://cashel.ie/
I know you'll be in Dublin. I could give you a laundry list of things to see, so I'll only recommend the three most meaningful. I strongly recommend a visit to the Irish Writers Museum, seeing a play at Gate Theater and drinking as much as you want on a literary pub crawl.
Again, my deepest sympathies, but you're on the road to a great future because you're going to visit Ireland.