ROBERT F. KENNEDY ready to propose to his GF actress Cheryl Hines.

The 58-year-old attorney and environmental activist is eager to put his estranged wife Mary Richardson Kennedy 's tragic suicide firmly behind him and start a fresh chapter in his life with his new love.

"Robert has already bought an absolutely stunning engagement ring and is now in the stages of planning the perfect scenario in which to propose to Cheryl," a source close to the Kennedy family told RadarOnline.com

"He knows she is the woman he wants to spend the rest of his life with and he wants to seal the deal as soon as possible and prove to her how serious he is.

"Robert is aware though that it hasn't even been a year yet since Mary killed herself and he doesn't want Cheryl to be subjected to any negative backlash. She's an innocent party in this whole mess and he wants to shield her from any criticism as much as humanly possible.

"Although he accepts that publicly he has to maintain an appearance of mourning, he points out that their marriage had been over for a long time at the time of Mary's death and he is more than ready to move on now and marry again."