Several years ago, in a conversation that will be burned into my heart forever, my dad turned to me from the passenger seat and asked, “Do you think I am stupid?”

I had already been trying to hold back tears, trying not to show any emotion in front of him. I wanted to demonstrate both strength and compassion in response to what had just happened to him. The best way to do that was to keep my eyes forward and focus on driving.

We were driving home from the VA, where a not-so-sensitive young doctor put him through the wringer. They first went over the scans of his brain with me, where they told me he showed signs of Alzheimer’s, pointing to the ridges and dark spots. But they added another layer of complication. In the area of his brain that controls speech was a non-tumorous cyst that caused him to be diagnosed with aphasia.

They explained that the cyst may have shifted, grown, or worsened due to Alzheimer’s. Nonetheless, it explained why we had had so many problems talking to us, and he did not understand what we were saying to him.

After reviewing the brain scan, the young doctor, seemingly ignoring the aphasia part of the diagnosis, started rattling off directives at my dad. You could tell he couldn’t understand what he was being asked to do. He was being ordered to remember and repeat a set of numbers, draw a time on a clock, and finish a square. These are standard tools doctors use in diagnosing Alzheimer’s and dementia.

During the test that seemed to go on forever, I kept wondering: If he had aphasia, how could he perform those tests correctly at all?

The little tests felt endless. My dad failed every one of them. It was like a gut punch to watch my rough and tough dad be humiliated.

Near tears, he asked if I thought he was stupid. I immediately said, “No.”

Tears welled up in his eyes. My dad, in all my 46 years of life, has never cried that I know of, but at this moment, one of the most vulnerable of his life, the tears began to flow.

Since that day, I have watched my dad transform. Pieces of him fading away. The Alzheimer’s creating more bad days than good.

But we have our moments. The moments where he jokes and laughs and I know those pieces of him are still there. When going out to dinner, he and I will have a margarita, and he enjoys the idea of being treated like an adult, like we don’t see anything wrong with him.

He can’t tell us what he’s thinking or feeling, and we find tricks and other ways to try to get him to understand us. In living with us, his grandsons go along with it, laughing, joking and being patient with Papa. He calls my youngest son “little guy” – because he can’t quite remember his name.

For me, I love having my mom and dad in my house. I love that I get to see them every day, but that comes with the tough side of an unforgiving disease.

For me, every time he has a bad day, forgets something or someone, or couldn’t say my name one day, it’s another reminder that my dad is fading away, albeit slowly. For now, it’s at a pace I can cope, but at the back of my mind, I know that won’t always be the case.

Before his diagnosis and the year after, for Father’s Day, I often took him to Rockies’ games. However, it’s becoming increasingly difficult to do such a day out. The walking, the stress of straying from his routine – he can’t handle it, as well as he once did.

In the challenging moments, I often talk to my kids about what their Papa instilled in me in growing up. I owe him my work ethic, my sense of humor, and my tendency to want to help others, even when it’s not so convenient for me.

My dad, a Vietnam Veteran, has always been the cliché version of tough. The only time he has ever put on anything resembling a suit was when he wore a tuxedo for me at my wedding. Needless to say, he took it off as soon as possible.

He worked overnight at Circle K, while he tried to get his plumbing business off the ground. When family members needed help, it was he who would jump in and pay the electric bill.

His hands and arms are stained from working long days in the sun, using tar and pipe glues and other chemicals, as he plumbed in piping for new homes and repaired existing ones.

Later, his arms got even more scarred and stained working on oil fields in New Mexico.

He would go to work today if he could. There are days you can tell he wishes he had a project or some hard work to do. In time, we found that coloring calms him and gives him a sense of purpose.

He has always been very family-oriented. On Thanksgiving and the Fourth of July, we had brutal family football games. I remember one year I tore the meniscus disc in my knee blocking my dad so my nephew could score. Family get-togethers were my dad’s favorite.

These days, when I sit with him in the evenings and have a drink, his smile speaks volumes. When my son jabbers to him, he may not understand, but he is content to listen.

Over the years, he has lost his ability to drive. He got confused on a walk one evening and no longer takes his walks alone.

As his only daughter and living with me, I manage everything. I am used to what I see changing in him. It’s tough every day to watch pieces of my dad fade, but on good days, I know he’s still in there. When he sees me upset, that hand he places on my back means more than he will ever know.

My bond with my dad has always been strong. And, on days when he can’t quite say what he means, a look, a touch, or a smile will keep me strong as we celebrate another Father’s Day, each one now more precious.

Thelma Grimes is the Deputy Editor of Colorado Politics.