Former beauty queen LIZZIE ARNOLD is refusing to become involved in a serious relationship with Nick Lachey, because he is still married to Jessica Simpson.

The 26-year-old Arnold and the former 98 DEGREES singer speak on the phone "virtually every day", but she has doubts about the future of their relationship.

She says, "We're good friends, but I don't know exactly where this is going.

"He's going through a tough time and we're there for each other.

"But I don't feel comfortable getting serious with a married man."

The former Miss Kentucky insists she's not in the market for a serious relationship.

A friend of Arnold's says she is proceeding with caution adding, "She won't get serious with him until he is divorced."