Getting in touch with old colleague?

I was recently laid off, and I'm no sure what to do. My former colleague doesn't reply to my emails. I've emailed him three times, each about three weeks after the other. In the emails, I'm asking for advice and if he has any suggestions on how I can sharpen my skills while I'm laid off. Even though he doesn't email back, when I call him he seems like he wants to talk to me. Last week, I asked if he wanted to go out to lunch sometime, and he said sure, some Friday. He said that he would call me when he was free. I've talked to people, and they said that he likes me. But, at my final meeting (exit interview) he didn't offer to write a recommendation (I didn't ask, but several other people did), and he said that he had to go to the gym and cut me off. I'm confused as to why he doesn't email back. I have always been nice to him. I said thank you and even wrote a note of appreciation. He's giving me mixed signals. He is 59 years old and I am 25. He wasn't my boss, but he was a friend in the workplace, at least I thought he was. What should I do? Thanks.