02/08/2012 09:34 am ET Updated Apr 09, 2012

Not Having Sex? 5 Reasons Why

As Valentine's Day approaches, there's always talk of the "romance" and "love" we are all supposed to feel. According to the media and the pressure we put on ourselves internally, it's also apparently time to have great sex, and plenty of it. The fact is that while magazines, blogs, and talk shows are full of advice about how to make your lover, friend-with-benefits, or one night stand explode with pleasure, lots of people aren't having sex as much as they wish they were. Let's talk honestly about why:

SLIDESHOW: 5 Reasons You're Not Having Sex

5 Reasons You're Not Having Sex

Dr. Marty Klein is a Palo Alto, CA sex therapist and marriage counselor. His new book from HarperCollins is "SEXUAL INTELLIGENCE: What We Really Want From Sex -- And How to Get It."

RELATED VIDEO: How Much Sex Is Enough Sex?

Knowing if There Is Enough Sex in a Relationship