A lot act as you have indicated, but many of us believe differently: https://www.amazon.com/Serve-God-Save-Planet-Christian/dp/0310275342
Yay! I, too, find God (or a "great spirit") in nature :). I think you'd really jive with the works of St. Francis of Assisi, the patron saint of animals and ecology. He wrote a beautiful hymn called "All Creatures of Our God and King," which is a great one to sing when you're outside and in awe of the wonder and beauty you see around you.
There's also Matthew Sleeth's "Serve God, Save the Planet." Does a beautiful job of explaining the role faith plays in the natural world, and vice versa.
In short, yeah, you should give it a try :). Presbyterian and Lutheran churches might be something you and your girlfriend would like, too; a little bit of "pomp" with the robes and whatever, but overall really chill and fairly progressive.