I’ve been avoiding this topic ever since Rob died because, as you can probably discern from the title, it’s always made me uncomfortable. Instead, I’ve written a lot of sad and beautiful words about my son, and how deeply I loved and continue to love him—from the day he was born until the day I die.

I haven’t written all that much about the other side of Rob’s story because it’s dark, frightening and confusing, and has always been kept hidden in the shadows of our family.

So here it is: Rob was mentally ill.

You wouldn’t know it if you met him. He was smart, engaging, cool and funny as hell. Over the years, he learned how to disguise his troubled mind and showed us what he thought we wanted to see, but it didn’t start out that way.

He was a cranky baby, an exasperating toddler, a difficult child, an angry teenager and a volatile adult. He was depressed for as long as I can remember and struggled with bipolar disorder from his late teens until he took his own life a few months ago.

Rob was first diagnosed when he was 17, and one of his shrinks told us at the time that he was also an alcoholic. We knew Rob smoked and sold weed and dabbled in other drugs (no big deal, back in the day so did I!), but I distinctly remember thinking the shrink was crazy, because that’s what I always did when it came to Rob. I chose to see what I wanted to see. I forever chose to view him in the most hopeful and positive light—the goddamn Esquire story was called “You Are Me,” for Chrissakes—even when everything he said and did pointed elsewhere. It was an act of self-deception that lasted until we lost him forever.

We always used euphemisms when we described Rob—difficult, impulsive, reckless, unpredictable, irrational, the unreliable narrator, that fuckin’ idiot—but we all knew the truth. Although I’m not sure he did. Sometimes he’d say he was having a bad day or wasn’t feeling good, but that was pretty much the extent of it. Whether it was out of shame, denial or just a lack of self-awareness, Rob never fully acknowledged that he had a mental illness. He admitted that he was an alcoholic the day I drove him to his first sober house about 18 months ago. And he texted Caryn two days before he died to say that he was depressed and needed meds.

The only other times we ever talked honestly about what was going on inside of his head was when he was in crisis and we were forced to­. The first instance was when he was 17 and we had sent him to a mental hospital for a month. Two Thanksgivings ago I drove him to the emergency room after he threatened to kill himself. They put him on different medications each time and each time he stopped taking them shortly after.

When we first talked about dealing with the disease, walking on familiar eggshells, he was defensive and belligerent. When we talked about it 10 years later in a psychiatric hospital on a 5150 hold, he was more compliant because he just wanted to get the fuck out of there. There wasn’t a whole lot of talk about it between those two incidents or after the last one.

And once he moved to L.A. it was really just about us being together. I never thought, Oh, I’m just chillin’ with my mentally ill, alcoholic son. Sure, I knew the disease was there. A lot of the times I chose to ignore it or gently navigate my way around it, and a lot of the times Rob chose to hide it, but for the most part it was just me and Rob shooting the shit, playing pool in a crummy bowling alley in Torrance and genuinely enjoying each other’s company. In the last two years of his life, I saw Rob at his best and at his worst.

I insisted on visiting him every Saturday afternoon when he was living in a sober house because I needed to see him with my own eyes. I needed to see what he looked like and how he was acting (in every meaning of that word) and it was generally just my way to tamp down my own endless worry and anxiety. I was also on the lookout for any clues that he had fallen off the wagon and possibly gone off the deep end again.

Mental illness isn’t always obvious, even when it’s staring you in the face. Even when it’s talking to you and saying crazy things, it’s easy to make excuses and rationalize what you see and hear. And that’s what I did while he was out here, because it was easier, because it kept the peace between us, because it kept him close to me.

A few months before Rob died, I remember telling my therapist that I wished I had the guts to just be straight up with him and say the following:

You need to go to a doctor and get meds for being bipolar. You need to get it under control. If you look back at when you’ve had horrible shit happen to you, it’s always between October and December, and that’s when you get manic, and you need to do something about that or it’s never going to change. You also need to take anti-depressants. I’ve been there, dude, I know how it feels and meds help! Go get fuckin’ help! Go get fuckin’ help before something terrible happens! I love you, you fuckin’ idiot!

I didn’t say any of that to him when he was alive and it’s one of the things that will haunt me forever, even though I’m aware that it wouldn’t necessarily have done any good or changed the way things played out. Rob was sick and the sick part got lucky and got what it wanted.

It’s not like we didn’t try to get a handle on the situation. We tried plenty. When Rob was little, maybe three or four, Caryn and I took him to see the first of many doctors. This guy came highly recommended: He’d written a best seller called “The Difficult Child” and specialized in hard-to-raise children. I can’t remember exactly what advice he gave us at the time, but he certainly didn’t help us all that much or suggest that Rob had mental problems.

“Your son marches to the beat of a different drummer,” Caryn remembered the doctor saying when I asked her about it the other day. “I also remember that his daughter called while we were in session and he said something like ‘She’s 19 and still difficult!’”

Back then, we thought that Rob’s angry and often out-of-control behavior was unquestionably about the emotional trauma of being adopted, which helped us explain why he constantly lashed out at and terrorized Zach. And sure, maybe that was partly to blame.

So was his crappy genetics. His biological father was in prison when he signed over the rights for us to adopt, and we knew that he had a violent history. We also knew that Rob’s biological grandfather had been a drug addict for most of his life. Despite it all, I will go to my grave thinking that adopting Rob was the best thing we ever did, although nature and nurture are two words I’ve come to despise.

And now the thing we never talked about is the only thing that makes any sense of Rob’s death. It’s the only thing that explains everything. Caryn was having a particularly rough day last week and couldn’t stop crying. I did my best to console her, as she has done for me many times, but nothing made her feel any better.

“Babe, whenever I’m feeling how you’re feeling, every time I beat myself up for something we did or didn’t do, the only thing that makes me catch my breath are two words­,” I said. “Mental illness.”

“You’re right, babe,” she said. And then she stopped crying.