Right. I waited. You just spammed us and split .

You're a spammer.

Oh for God's sake. I looked at your Website.

I gather you don't read much, or look at Websites. Have you been to a book store lately?

Even the blurb is cringe-worthy.

Reasons for marital strife are endless: changes in personality, boredom, alcohol, loneliness, money issues, midlife crisis and in some cases an affair.
* If the reasons are endless, then you can't list them. You list them.
* You've set up a series of parallel clauses, which you then rupture with a clunker at the end:
and in some cases an affair
* Also these aren't reasons; these are causes. Reasons make it sound like these are reasonable ways to behave in a marriage. Let's try that again:

Causes for marital strife may include personality changes, boredom, alcohol, loneliness, money issues, midlife crisis—even infidelity.

Mind, book blurbs are a very specialized kind of copy. A good publisher has people on staff who excel cover copy; I'm not one of them. But this isn't even in standard English. It's just plain awkward.

When a marriage fails, it is more than likely that both partners are responsible for not taking control of their relationship by insight, patience, commitment, humor, flexibility and hard work.
This isn't making me want to read the book. It's making me wince. It doesn't make sense.
* You can't "take control" by "insight." I'm also not sure you want to use "take control" in the context of marriage unless you're writing within the BDSM communities.
* You want to make people pick up the book and read it because it offers help. This copy is scolding the readers—who were potential buyers. They're going to walk away and not even open the book.

Successful marriages involve two people who are willing and have the courage to actively explore ways to communicate and do things better. Marriages do not succeed due to some outside force.
I can tell you're a Psychology major just from your prepositional phrases. People, the grammatical subjects performing the verbs, are distanced from the verbs. You want to have people doing things. Things your potential readers could do to help their marriages.
Put the people at the front of the sentence. Having them doing things.

The power to maintaining a healthy and happy marriage is within each partner.
Yeah, that's not even English. You don't use the infinitive with a present participle.