I agree with most other posters--if you want her to go, you should pay for her to go. If you want her to pay, you can invite her, but don't expect that she can afford the trip--she'll likely say "No".
Every family is different. My DD24 loves to travel. Sometimes she travels with us and we pay, sometimes she travels on her own and she pays. For example, we went on a family vacation last week. She was invited (and we would have paid), but didn't go. Instead, she's in Alaska, hiking with her boyfriend. They don't have a lot of money, so it's a camping/hiking vacation, versus our all-inclusive one. She's perfectly happy with her decision, and judging by the photos, they're having a marvelous time. I should mention that she's also a college graduate with a full-time job who lives 800 miles away from us, so mostly independent (we still have her on our medical insurance).
She will be going on a 12-night cruise with us next summer.