Yeah, think of "dake" as just in the sense of "exclusively/only doing/nothing less than" and "tada" as "simply/merely/nothing more than"
Some others for the OP if she ever returns...
1. Anata ni totte, watashi wa warui hito (hito ga
warui) kamoshiremasen.
Watashi wa, anata ni totte warui hito kamoshiremasen.
Anata wa, watashi ga warui hito da to omotteiru kamo shiremasen.