Speaking on the 'Ellen DeGeneres Show', she said: "He has this incredible family. I am as in love with his family as I am with him, which is an extraordinary sort of gift. You never take that for granted … It really is an absolute blessing. I feel very lucky. They’re incredible people."
The couple – who met at a party - are still "figuring out" their marriage plans following Will's festive proposal, but Drew is sure she's found the right man for her.
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The brunette actress - who was married to bar owner Jeremy Thomas for a month in 1994 and comic Tom Green for five months from July 2001 - added: "I just feel really lucky and really happy and really calm. Which is a really wonderful feeling."
Even though the couple are yet to make any major plans for their nuptials, the pair have found time to adopt a puppy called Ollie from a Los Angeles rescue centre.
Drew explained: "He looks like a bear. I can't even handle it. He was a rescue dog. He was found in a box with his brothers and sisters outside of East Valley Shelter."