If you believe in an afterlife, why is it hard to believe that those in the afterlife might be able to communicate with some individuals? I know many people who have mentioned feeling comforted by their loved one's spirit, or feeling a warmth and just knowing the dead person is near. Is that just wishful thinking/delusion, or can those who've died maintain some kind of contact with those who are still alive? 
I had a christmas cactus for about 8 years, and it never, ever blossomed. Didn't matter what I did, which suggestions I followed, the darned thing was HUGE but it never blossomed. One fall, my bff Diane was diagnosed with pancreatic cancer, and we knew her days were numbered. Several months before she died, Diane said if there was any way to do it, she was going to return in spirit to visit me. I told her no way, too scary, but if there WAS a way to maintain contact from beyond, she could make my Christmas cactus blossom. Diane died on the last day of August, 1988. My Christmas cactus blossomed every after that, for 17 years. In spring of 2005, I had a dream that I met a little girl on the beach. She looked at me and said, "I'm Diane, who are you?" I woke up, and realized that I felt calm, and that Diane was OK. My cactus never blossomed again. Wishful thinking? My sub conscience? Coincidence? Who knows? Regardless of whatever really happened, I found peace and comfort in this.  
Is there any way to really KNOW for sure if there is contact from spirits or not? Like so many things, it's all a question of belief. If those who are suffering in their grief believe that Theresa brings resolution, peace, and comfort to them, isn't that good?