Do you think It is okay to go to the park with this guy i used to date when i have a boyfriend?

we were never exclusive. i USED to be in love with him. we dated for a year, but he never wanted a full committment. but now im totally over him. me and him occasionally have moments where we tend to 'click' but overall we werent arent that compatible. Me and my boyfriend havea lot more common intrestest. the guy i used to date casually called me up to go to the park and i said yeah mabye because my boyfriend has been MIA for almost 2 weeks now since hes friend died and he doesnt really want to be around anyone. its good that im hanging out with the guy i used to date so i wont be lonely while my boyfriend is trying to cope with his friend's date