What does he think of me?

I have known this married man for 2 years. He is 54 and i am 36. He invited me round to his house for a coffee one morning in December 2013. It was a quick visit as I had things to do. We had a chat and a laugh. That night he text me to thank me for going to visit him and as I rushed away he asked me to go back again. We texted for most of the night and there was a lot of flirting going on. I went back over the next morning and we talked about how we both have really liked each other for some time. He sat beside me and we kissed which then lead onto other tame things.
From then we have been texting each other a lot each day. At the start, it was him sending me the most texts and would type things like "just to let you know I'm thinking about you". It is very flattering as I never thought for a minute we would get together. We meet up as often as we can too.
I get a morning text every morning from him. He recently got promoted and is working varied long shifts. since then, I have noticed a bit of a change. It's gone from 20+ texts to sometimes about 5 a day. Im thinking its cos he's up early and he goes to bed early and is working (driving).
His texts used to be so lovely and he'd tell me how beautiful I was, often, along with loads of other compliments and flirty banter. But now they are not as often and getting quite boring although every so often there will be a flirty/nice comment there. He phones me when he can and we meet up once a week when he can. I did mention that I thought he was loosing interest in me he said no way, why did I think that. It's all good. He'll never get fed up with me.
I have fallen for him big time and cant stop thinking about him all day. He is so kind and nice to me when we meet and looks at me often, compliments me, holds my hand, feels relaxed, but I miss the texts he used to send. I'm wondering why he's like this. Like he's hot and cold. I used to get <3 and xxx after texts but i dont get them as often now. I don't understand why. He told me he's not lost interest.
I know what we're doing is wrong but as I split with my fiancé of 16 years over a year ago, getting all this attention and having his company is really helping me get over my break up.
If he was loosing interest, why not just say or why not just stop sending me texts or stop asking to meet up with me... And advice/comments are appreciated.