I have hsv-1 antibodies in my blood. What does that mean? Am I immune to getting herpes?

Past exposure. First, remember that hsv-1 is actually quite common as this is the comon "cold sore" on the lip. The antibody in the serum simply implies past exposure. No-one is "mmune" to herpes as the virus can reactivate at times. It is possible for hsv-1 to present as genital herpes, but this is less common as hsv-2.
Infected, not immune. It means that, like most people, you've been exposed to hiv-1 and have it in your body. If you ever get cold sores (fever blisters), that's hiv-1.