Maybe it's just like a relationship with someone you're dating and mabye it's just normal and not something you need to worry about. I just think that maybe you got worried when you stopped feeling the same excitement, and that nervousness is blocking what you feel now.
Maybe it was all normal though, in the begining of a relationship things are more exciting, as you know nothing about the person (deck) involved, it's a period of discovery and uncertainly (how will they/it react to me, how will I react to them/it)....then after a while you get to know each other and become able to predict how they/it will react, to know what to expect.
Predictabilty and knowing what to expect are parts of getting to know someone/something better. You know how they/it things, it's personal psychology. But that is not a bad thing in any way.
In a relationship when that initial period of excitement ends, comes the good times. The times of deepening love, of knowing you can always depend on the person (deck) in good times as well as bad, the accumulation of a series of beautiful memories together.
I just think that you entered another phase, and that is where you are heading now.
BTW, I think a good idea might be to ask. Do a reading to ask how you and the Thoth can feel like friends again, or phrase it how you would like. Even if you have to do it with another deck, just ask.
Babs