Hi, two days ago i updated my mac to 10.14.6. After i noticed that the adobe Lightroom icon is gone from my dock, while photoshop ist still there and functioning. I updated the adobe suite after, open it lightroom and all all my setting and my catalog disappeared.
You are probably opening a new catalog, not the one you were working on with all your photos in it. Usually LR catalogs (on Mac) are in your User folder/Pictures. Look in there for your original LR catalog folder, open it, double-click on it to open.
You could also try launching LR and, in the File menu, go to Open Recent and see if your other catalog is there in the list.