I just saw a friend at the dog park whose mother died about two weeks ago. I had seen the news on Facebook. Instinctively I greeted her with a warm, wordless hug, the one that says, “I’ve been there. I understand.” The greeting that has become all too common among women in later middle age.

Like my mother — who died on September 24, 2015 — this woman’s mom had suffered from Alzheimer’s disease. We commiserated over the reality that our mothers had not been themselves for years. “I have to go back to 2011 or even 2010 to remember when Mom was really Mom,” I told her.

And for a moment it was back, the wistful sadness I have held at bay for 13 months. As I looked at Jill’s tight smile and moist eyes, as I listened to her describe crawling into bed with her dying mother — allowing her mother one last chance to be a mom — I felt my stomach drop and my throat catch. I wanted to see my mother one last time.

Is this grief? I can’t tell you. I don’t know how to grieve. All I have done since she died is to keep busy, keep moving forward.

“Grief can be exhausting or a relief,” says a handout from the hospice whose nurses cared for my mother in her final days. A bereavement coordinator sent a large refrigerator magnet that I stuck in a pile of papers. It reminds me, now 13 months later, to:

• Take some walks: Check. I walk to work.
• Stick to a routine: Check. I’m a creature of habit.
• Create soothing bedtime rituals: Check. I go to sleep at night listening to music or a podcast.
• Do some activities you enjoy: Check. I’ve been practicing yoga more often since Mom died, and my husband and I rescued a wildly affectionate puppy at the Animal Humane Society 10 days after her funeral.
• Expect a wide range of emotions. OK, but what if I can’t find them?

I have dreamed once about my mother in the year-plus since she died; she was old and gaunt, and she had cancer. Maybe my guilt was speaking to me. I was relieved — and shocked, and sad, and scared — when she was diagnosed with blood cancer a mere four weeks before she died. For her, it was a release from the indignity of her decline. For me, it was the end of having to watch it.

My younger son, Nate, recently asked for the code to my iPhone. I told him it was the date of Mom’s death. He paused and turned to look at me. Nate is a truth teller, and I cherish our feisty and fearless conversations. “Do you think you would cope with this better if the code was her birthday instead?” he asked.

Good question, though I never did respond. First, I have to think about what mourning means.

One year after our mother died on a windy autumn night, my brother posted a photo on Facebook of himself and Mom. They look young, happy and vigorously alive. “We need happy memories today,” I responded. But in truth, I cannot access them.

My memories of Mom are either grim or morbidly amusing, like this anecdote I jotted down in August 2012, six months after we learned she had Alzheimer’s: My brother consulted a colleague whose mother-in-law has advanced Alzheimer’s. The woman told my brother that obsessions are common at this early stage. We should be grateful that our mother is obsessing about her checkbook, she said — even though it drives us crazy. Her relative became obsessed with constipation, and talked people into giving her laxatives and prunes daily. “I laughed, too,” my brother said as I tried to choke back my guffaws. “But my colleague’s father-in-law had to clean up the bathroom every day.”

My friend Janey, who was like a daughter to my mom, recounted the details of caring for a frail, 91-year-old parent only weeks before her own mother died. I was reminded of the daily schedule, the frequent phone calls, the sense of helplessness, the constant worry.

Now, all I have left of my mother is photos and the purposeful distribution of her possessions. “It’s so unreal,” I wrote a former colleague whose mother died recently. “The person who has loved you unconditionally, who’s known you literally all your life, who was your greatest cheerleader and supporter — suddenly she’s gone!”

I sift through notes, the abstract musings that I can’t seem to stitch into a cohesive whole. None of them are dated, which accurately reflects the confusion and unreality of the three and a half years when Mom gradually slipped away and then suddenly, traumatically left us, gasping for air, bone thin and incoherent in a morphine haze.

Here is where I can start to pinpoint my version of the stages of grief:

• Reflection: “As my mother goes blank behind the eyes — as the light of her intellect dims — I am thinking about my role as a caregiver and about how it didn’t end when my children were grown. I never dreamed that I would have to care for her.”
• Resentment: “My aunt died in her sleep in June, with no apparent warning. Hard as I know that was for my three cousins, I envy the simplicity, the lack of ambiguity. When will this be over?”
• Resignation: “In all the years of dealing with my mother’s weaknesses and neediness, I’ve never thought about how much I needed her.”
• Regret: “I’d like to do it all over again, without the whirlwind and the fear. I’d like to be more present for her dying.”

I didn’t want to lose my mother, but it was time for her to die. I still wrestle with that potent mixture of regret and sheer relief.

“It’s a complicated grief,” says the minister who performed Mom’s funeral service last October, “because dementia is an incremental death. She was both here and gone. You experienced her physical presence but her psychological absence. There’s no possibility of closure or resolution.”

My companion and my confidante, my caregiver and then my charge, my mother was present for every significant moment in my life. I have to live with the reality that I was often at my worst with her.

Maybe, in the end, that is where grief leads us, toward perspective and acceptance, seeing our loved ones and ourselves as perfectly human, imperfect people. “Yes, Mother,” wrote Alice Walker. “I can see you are flawed. You have not hidden it. That is your greatest gift to me.”