The former 'Beverley Hills, 90210' actress and actor Dean - who have four other children together - have endured some rocky times, including 51-year-old Dean's affair in 2013, but Tori admitted they have pulled together for the sake of their family.
She told PEOPLE: ''I feel like Beau is really the pillar of the rebirth of our relationship because our relationship had to crumble for it to be rebuilt and it was really important that we just start it over.
''I think Beau is a symbol of that because he's the first baby out of all five that we're raising in a communicative way.''
Tori and Dean - who starred in their own reality series 'Tori & Dean: Inn Love' - married in 2006 and are also parents to Liam, 10, Stella, nine, Hattie, six and five-year-old Finn.
The 44-year-old star admitted she has learned a successful relationship takes hard work.
She said: ''I look back and I remember doing interviews probably seven years ago ... I was like, 'It's easy, we don't have to work at it. We have this great marriage.'
''Eleven years later, I'm like, 'It's a lot of work.' It takes work and I took that for granted - I think we both did. We thought, 'Oh, our relationship just works,' and the truth is, no relationship just works.''
Tori revealed one of the most important things she had learned was to talk about her feelings.
She said: ''I really feel like I found my voice in the relationship. It was really empowering for me because my whole life I grew up and I never talked about my feelings ... so I carried that into my relationship.''
Tori has previously admitted she would love to have another child with Dean.
She said: ''I do like even numbers and I was always a big fan of The Brady Bunch.
''So three boys, three girls would be ideal. But we're blessed and you know, who knows?''