is this an affair or what?

I have no idea if this is an affair. But we have been talking/texting for almost 2 years. Both married and we are 20 years apart.. we are looking for fun, nothing more. We have met after we both out of work, only if we had time to spare. We would not go out of our way to see each other. He has been asking me recently to meet him during the weekend. I just don’t know what to say because I really don’t have the time, But anyway, on and off we have been telling each other not to speak to each other in that manner. He would cut it off or I will because it is too much. But every time we do, we end up talking again.. We haven’t had sex,I Can’t ever go that far. But he has asked me. We have kissed but then decided that kissing would cause intimate emotions that we don’t want. We have touched each other, we video chat even at times he wouldn’t have have a boner or I wouldn’t be horny but we would just show each other off. We have had some normal conversations, even about going to a resort together. One time when we stopped talking, he started coming around and he asked me “if I don’t like him anymore?” I said that’s not true. He has vented to me about things. And no, we don’t talk trash on our spouses or family. We both respect each others families. There is so much I can type about but it would be too long. Anyway recently we were having a conversation, he was joking around saying that I (me) should stop this silliness and I said, I should and I meant it. So we stopped talking for a few days but he would randomly im me with smiley faces and I wouldn’t reply. Then one day he texted me saying “ I am glad you are being good! Is it difficult?” what does this mean?
And I replied “no”
And he said…”keep up the good work! I am too weak.”
All I said is “you’re not”
What is he trying to say? Is this an affair? I am so confused. It has only been a day since he texted me this…I just hope he doesn’t reply back
One day or more I told him that I don’t want to have fun anymore. And he just asked me so many questions and if he did anything wrong. Ect he just beats around the bush.
Really, what is this situation. I m pretty sure so many people go through this especially for attention. But we keep IT discreet. Im not the clingy type and he seems the same. So its only if we ever have time. Sorry if any of this doesn’t make sense. I have not told a sold about this situation. SO I REALLY NEED TO VENT THIS OUT.
And if anyone have questions for me, feel free to ask..