My BFF and I broke up 3 years ago and he's started calling me. Thoughts?

We have been BEST friends for 10 years (we were friends prior to that but we became closest during his divorce when he needed a shoulder and our friendship wasn't hindered by his wifes insecurity). He even moved in with me during the divorce because he had nowhere else to go and I lived very close to where we worked. Eventually it became a romantic relationship but we decided we were better off as friends. We took "family trips" together taking his two daughters with us. I eventually got married. His daughters and I remained close and they came to stay with me on weekends when he had a date. He eventually started dating a mutual friend of ours (we all worked together at one time). She and I were cool but as they got more serious she told him she thought it was inappropriate to be friends with someone "like me". I've always been there for him through thick and thin. He and I dissolved our friendship because of the jealousy of this person. His oldest daughter and I have remained close. I took her to Mexico for her 18th birthday (which was her first birthday not being bffs with her dad). Now she's 21 and I haven't spoken to her dad in over 3 years. He just called me this weekend asking if I'd call him back. I think it's a temporary fix. Like he and the girlfriend have broken up and he needs a bandaid on his boo boo but as soon as they get back together he won't be "allowed" to talk to me anymore. I was very hurt over our breakup and don't want to go through it again. I did call his daughter this weekend and asked "What's up with your dad? He called me today. Did him and Chris breakup or something?" and she replied "Yes, they did breakup." So there it is. I miss him but I can't go through it again.