Jessica Simpson doesn't think love is enough to sustain a relationship.
The fashion mogul, who divorced her first husband Nick Lachey in 2006, and previously dated singer John Mayer and NFL star Tony Romo, thinks her long-term relationship with her fiancé Eric Johnson works because she is the yin to his yang.
The 33-year-old star told the February issue of Redbook magazine: ''I've learned that sometimes love is not enough. You can have a soul mate and be madly in love with that person, but it's not necessarily enough.''
Jessica and Eric, who have a 20-month-old daughter, Maxwell, and six-month-old son, Ace, together, are planning to tie the knot later this year and she isn't worried about their future because they have great communication.
She said: ''I think you have to have personalities that mesh well. You have to be the yin to their yang. You also have to be open to figuring things out together and communicating even when it's the last thing you want to do.''
She added: ''I have to admit, it doesn't hurt that Eric is one of the hottest men I've ever seen and he looks amazing naked!''