The Playboy founder admits he wasn't expecting that the blonde beauty - a former Playmate of the Year - would ever separate from the actor because they seemed so well suited.
He said: "I don't think any of us saw it coming. From the outside looking in, it looked like a magic couple. I thought she found the right one."
Although the 84-year-old media mogul hasn't spoken to Jenny about the split, he is confident she will bounce back.
He added to People magazine: "She's a strong person."
Jim announced on twitter last week that he had split from Jenny - who has an eight-year-old son Evan from a previous relationship - after eight years together.
He tweeted: "Jenny and I have just ended our 5yr relationship. I'm grateful for the many blessings we've shared and I wish her the very best. S'okay!
"Be of good cheer folks! It's a beautiful world, and we're all gonna get what we need the most! (sic)"
Jenny also took to twitter to reveal news of their split, saying she was "grateful" for their time together and would continue to be "committed" to his daughter Jane, 22.
She said: "I'm so grateful for the years Jim and I had together. I will stay committed to Jane and will always keep Jim as a leading man in my heart."