(CNN) For decades this Philadelphia physician lived a life inside his head, rarely expressing himself with his heart. He says his inability to open up wasn't good for his first marriage, or his second.
"I did not want to get divorced again, did not want to go through this thing with a broken family with kids," he says. "That was really very painful the first time."
This father of five, who wants to remain anonymous for his children's sake, looks back on his life and the mistakes he made.
"I frequently made assumptions and would mentally go over things in my head at home, all the time assuming that for example my wife was thinking or feeling something without asking her or checking in. I was living in sort of a delusional land for a while."
He says he felt frustrated about how to develop more intimacy in their relationship. Things got so bad that his second wife asked him to move out of the house.
"It was really a horrible experience," says the man, now 71. "It was lonely. I could be in my head all I wanted but it was deafening silence, lack of any kind of closeness... that actually helped me define what I really wanted primarily in my life, which was my relationship with my wife."
That was more than 20 years ago. It was a turning point that saved his marriage.
He and his wife went to a marriage counselor, but that wasn't enough to bring him out of his shell. Nor was one-on-one counseling.
So a therapist, psychiatrist Dr. Rob Garfield, recommended he join his "Friendship Lab," a therapeutic group of 5 to 7 men who learn how to become more comfortable opening up about their problems. They meet every other week with Garfield and his co-therapist, Jake Kriger, at the Men's Resource Center in Philadelphia. The two developed this model of group therapy 20 years ago.
"These are the same guys in their own community that can be functioning fairly well but personally feel disconnected," says Garfield, author of the 2015 book, "Breaking the Male Code: Unlocking the Power of Friendship."
Several of the men in the group have been members for more than 10 years. It helps participants learn to trust one another, communicate and open up.
Garfield says this physician who suffered from isolation is far from alone. He finds that many men, middle-aged and older, are a product of generations of male "coding."
"This is the way we're supposed to be: emotionally restrained, keeping things close to the vest, being in control, independent, competitive," he says. "These start from the time we're kids, as early as the age of three, and are reinforced through adulthood: the boy code, the guy code."
Garfield himself had great difficulty opening up decades ago. He went through a divorce and was starting a new career in his twenties.
"In men's group, it really accelerates their progress because they're getting support and actually hearing themselves kind of mirrored by other men, who on the surface look pretty good but are going through the same things," he says.
The Philadelphia physician, who asked that his name be withheld out of privacy concerns, has been a part of the friendship lab for 20 years.
"It's just a main venue that's safe for expression for anything that you wanted to bring up with the idea that you're not going to be judged, you're going to be heard, that you're going to get honest feedback from guys that you know, respect and like," he says.
"I didn't tend to have sustained relationships with men that would allow me to get into a lot of this personal information. I never had problems per se relating from a guy to a guy. As far as relating some of these issues, there wasn't really anybody I would trust. That I could tell them about anything that was on my mind."
Garfield, who teaches in the Department of Psychiatry at the University of Pennsylvania, designed a national survey in 2012 with a research group looking at the friendships of 380 men from a variety of age groups, races and ethnicities.
"Most guys have friends. In general the research shows men have as many friendships as women have but the quality is often very different. If a guy tells you he has a good friend, he may see them once every 3 to 5 years," says Garfield.
"What they wanted was more emotional intimacy in friendships to be able to express their feelings more."
Some men might also worry they will lose their romantic partner's respect by being too "soft." Garfield disagrees.
"My experience in getting feedback from women is that it's a relief. They're not thinking this guy is turning into a wimp," he says. "He's actually present and accounted for. He's showing up."
Dr. Garfield says one of his roles in the Friendship Lab is to help steer the men to talk using a language of emotion.
"Some men are actually able to do this fairly easily. Other men have to learn words like sad or shocked or hurt, these kinds of feeling words that actually put them in touch with raw emotions that they're feeling," says Garfield.
Garfield says the price of not opening up is not just profound depression but illness as well. Some men come to the group complaining of gastrointestinal problems or other issues like drinking too much.
"Many of these guys have physical kinds of problems that they don't really understand is connected with their isolation," says Garfield.
The Philadelphia physician says it took months to begin to trust others in the group, but after years that included annual sailing or other bonding day trips, he began to open up knowing that what they said in group was confidential and safe.
"The group itself is brutally honest. We're very interested in not discussing fluff in any way or small talk, and if someone is having a hard time expressing where they are, for whatever reason, it becomes pretty apparent because you've been working with these people for years. There's no hesitancy to call somebody else out to say listen, 'This really is not you. You're really being inhibited. What's going on?'"
Today the 71-year-old says he truly has happiness in his life because of this group.
"This is the best I've ever felt, which is really good. I feel more like a whole person rather than a shadow," he says.
"I felt grateful that they were giving me honest feedback so I could get out of my head and more into the reality of what was going on in my life. I think it was like peeling away sort of an onion, a little bit at a time."