Where do you draw the line?

I had the pleasure of interviewing Daniel Smith last week in advance of his visit to Marin. Smith is the author of “Monkey Mind“, a painfully honest an extremely funny account of what it’s like to live with debilitating anxiety and its destructive absurdities.

In it, he describes how he lost and then won back the woman who became his wife.

When we kissed for the first time, again, Joanna pulled away and said, “Are you still nuts?”

“Yes,” I said, I’m afraid so. “But I’m working on it.”

Having a mental illness like Smith’s is a challenge; so is loving and living with someone with mental illness with an extra layer of angst,” you’re always walking a fine line between enabling and compassionate support, guilt and fear, anger and helplessness.

I know because I have a son who has OCD. But, as a parent, I have unconditional love for him; spouses don’t always feel that way toward each other.

About 26.2 percent of Americans ages 18 and older, about one in four adults, live with a diagnosable mental disorder in a given year, according to the National Institute of Mental Health.

That means there are a lot of marriages living with mental illness.

Marriages in which one spouse is depressed are nine times more likely to end up in divorce, according to Laura Epstein Rosen and Xavier Francisco Amador, authors of “When Someone You Love is Depressed: How to Help Your Loved One Without Losing Yourself“.That’s a pretty depressing number. It isn’t depression itself that sends a couple to divorce attorneys, however, but the consequences of not addressing the depression, experts say. And most of us aren’t very good at that.

“Our loved ones see our illness far differently than we do,” writes John McManamy, an award-winning mental health journalist and author who has bipolar disorder and blogs at McMan’s Depression and Bipolar Web. “We may complain that they don’t understand us, but far too many of us fail to recognize the horrible abuse we have put them through.”

It isn’t easy living with someone who has a mental illness, nor does everyone reach such a happy ending as the story of John Forbes Nash Jr., a Princeton mathematician and schizophrenic who was the subject of 2001’s “A Beautiful Mind“. Often a depressed spouse withdraws or cheats. Sometimes the spouse of the depressed person feels responsible and becomes more of a caretaker than a partner. Not only is that exhausting, but it doesn’t make for a happy, healthy marriage.

Even treatments for mental illness can cause problems in a marriage. Many of the meds can impact a person’s sexual responses and desire. Plus there is still a lot of shame and guilt surrounding mental illness, although there’s more awareness now than ever before.

If depression continues for a long time, a spouse may get tired of dealing with it and seek a divorce, according to Constance Ahrons, professor emeritus of sociology at the University of Southern California and author of “The Good Divorce“.

I was surprised to discover that the rates of divorce for people with OCD are relatively low, just 3 percent to 5 percent. This bodes well for my son, thankfully, should he marry one day. But divorce rates for those with bipolar are much more sobering; about 90 percent of marriages in which one person has bipolar end.

Which couples are most likely to stay together? Those who acknowledge the illness and keep talking with each other about it. Spouses have to know where to draw a boundary line, as long as they realize that that line is constantly going to have to be redrawn, says David A. Karp, a sociology professor at Boston College and author of “The Burden of Sympathy: How FamiliesCope with Mental Illness“.

Sometimes, spouses just have to withdraw. If they don’t take care of themselves first, they won’t be able to take care of others.

While it may seem cruel to divorce someone who’s mentally ill, part of removing the stigma of mental illness is accepting that everyone, mentally ill or not, is not only marriageable but divorceable, too.