When my mom died last year, people were kind. It's quite natural to want to comfort someone when they lose a loved one. The problem is, there isn't anything you can say that actually helps. You can, however, be annoying while not helping, or just be kind while not helping.
In the first category, we have all the variations of "She's in your heart" or "You'll always have her with you." Fine. True enough, and nearly a year into it, I'm beginning to see what you mean. But in the thick of grieving, this is somewhat like telling someone who just lost their eyesight that they can at least remember what things look like. I don't want memories of my mom in my heart; I want my real, loving, creative, pain-in-the-ass mother in her own damn house. Same with telling me that the pain will recede with time. So, you're saying you suspect I'm a callous traitor? Now that time has passed and the pain has, yes, receded, I know that this is basically the only way we as a species, let alone me as an individual, can carry on. But to tell me in the weeks after my mom died that I would not always be in pain felt like an accusation of betrayal. Mom doesn't get to move on from being dead, why should I get to move on from grieving?
And don't even get me started on the "God's plan" or "God needed an angel" people. Come one, seriously? God needed a bunch of dead Rwandans, everyone who was on a beach in Thailand during the tsunami, dozens of teenagers in a Colorado high school, that little kid whose stepmom murdered him last summer--AND an old lady with limitless energy but limited patience? The idea that there is a God who goes around intentionally slaying people in order to get more harpists is so not a comfort. Luckily, I don't know many people who went there.
Here's what is helpful. Say something. Yes, even if you say something stupid. I resisted rolling my eyes because I knew you were trying to be kind, and it sucks to want to help when someone is dead, because you can't. But out of the grey fog that surrounds the entire time mom was sick, then in the hospital, then dying, then recently dead, I have surprisingly clear recollections of who realized the impossibility of consoling me and gave it a go anyway. The first sympathy card I got was from the mom of a woman I've been friends with since 3rd grade. Our moms hadn't even seen each other in 20 years, and I've only seen J. a few times in there myself. But she sent me a card, and it was so sweet, and I will always think even better of her than I did before. My godparents sent each of us a letter. An old friend of my dad wrote a nice note about what that friendship has meant to him, my mom's childhood friend wrote several pages of recollections, and one of my friends who probably was briefly introduced to my mom at my wedding stopped by the house with food. I wasn't even home; I was staying with my dad, but just the idea that she took the time meant a lot. My dad kept all the sympathy notes he received in a little basket, and all of us went through them compulsively for a few months. Nobody can do a damn thing, but somehow it's still important to try.
Here's a funny story--well, okay, maybe not. After missing most of the December and a huge chunk of January, I went back to work. And nobody said anything. It was surreal. Then one woman, whose dad had died the year before, asked me out for a beer, and expressed her sympathy. I thanked her, and mentioned the eerie silence I was getting from the rest of our colleagues. She explained that our principal had asked everyone to respect my privacy and not bring it up unless I did first. I know he meant well, but wow. You need to say something, people. Acknowledge it. You can't fix it, but you can honor it by acknowledging it.
In all that time, I heard two things that actually worked for me. First, the day mom died, I posted her birth and death dates and a photo of her on Facebook. Then I instantly felt like an idiot, and posted a comment calling myself tacky for having done that. A FB friend, who is more of a distant acquaintance in the real world, responded with something she had learned when her own mom died. "There is no wrong way to grieve." I hung on to that thought pretty tightly. With three sisters and a dad reeling from the same pain, it didn't just help me deal with my own grief, but also helped me allow them theirs.
My husband was every (positive) cliche possible. Pillar of strength, shoulder to cry on, shelter in the storm--he took them all on. His dad died a year before we met, so he had wisdom to spare. Most of which he put to the wise use of not saying much. But he did tell me that what would be worse than the pain and sadness would be losing a parent and not feeling very bad about it. This didn't make much difference in the pain, but did at least make sense to me. Months later, I was in the middle of a group of people grousing about their mothers, saying how they avoided talking to her. I was briefly bitter, wishing as I do that I could talk to mine, then I saw my husband's point--I was so much better off for having had a close and loving relationship with my mom.
Ready for the recap? Avoid "God's plan" crap unless you know for a fact the person you're talking to really thinks like that (and while they might have before the death, they may be revisiting that, so maybe just avoid it altogether). Go light on the "you carry them with you," but if it's all you can think of to say, go for it. Say something, and not just once, but the next several times you see the mourner. And if it's you in mourning, however you're handling it is probably the right way for you. Unless you're, y'know, mainlining heroin or beating people up. (Bonus tip: alcohol doesn't help, but you'll probably try it a few times anyway, so you may as well buy a bottle of something you like.)