Like some people have mentioned, I play solitaire a lot with decks I feel I want to reconnect or establish a new connection with. Just handling the cards helps! Also, I enjoy going through the deck and reading either reading the LWB and making keywords (if the book is wordier), or just making new, more personal keywords and writing it all down. Looking at each card individually and really thinking on them often helps how you see the deck.
There's also the possibility that you just don't like the deck much anymore and subconsciously don't want to use it. That happens, and sometimes you just have to give it time~