The cockroach is read as survival against all odds, and also as something unwanted that keeps coming back however often it is swept away. Dream books link it to what you would rather not see in your own house — a habit, a worry or a mess left in a dark corner. One cockroach running across the floor is usually read as a small nuisance you keep noticing; a whole infestation as a problem that has grown while it was ignored. Failing to kill it, or watching it return, is taken as frustration with something that resists every quick fix. It can help to ask what in your days feels persistent, unwelcome and harder to clear than it should be.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.