Gifts returned after relationship breakup

What is the name of your state? Colorado
I Have acouple who had lived together for close to 2 years. The man purchases numerous pieces of expensive jewlery for her and also takes her on exotic trips and clothing. He trys to get her to marry him but she keeps saying no. they are never "engaged". Because of some of his shady dealings and lying, she leaves him. He now wants to sue for the value of all the jewlery and half of the cost of the trips. Also some of the expenses that were incurred while they lived together. The man is obsessive and calls her cell in the middle of the night. Also has been seen driving by where she now resides. Apparently, she has some information about how he did an insurance scam and extorted money from the company he now works at. With all that I guess I need to know the laws of Colorado and the Supreme Court on whether he has a case or not. I was under the assumption that "gifts" were not returnable under law. Is this considered a common law marriage? What are her options? Thank you

[Seanscott]

I think you're right - gifts are gifts. She needs to get a restraining order and tell him to "sue away".

Sounds like a psycho to me.

TELL HIM TO PROCEED WITH A LAWSUIT. SHOW UP AT THE SMALL CLAIMS HEARING SO YOU CAN LAUGH AT HIM AS THE JUDGE TELLS HIM WHERE IS THE CONTRACT YOU AND HE SIGNED THAT STATES IF THE RELATIONSHIP DOESNT WORK OUT HE GETS REIMBURSED FOR HIS EXPENSES