So first, and most important - when she was diagnosed, did you get tested and treated? You can have that for a long time without symptoms. You can also transmit it without symptoms. If you haven't tested for that, make that your first priority.
A red bump that has last 6 months isn't an STD. It could be a fungal infection, eczema, dermatitis, etc. When you get tested for chlamydia, show the doctor the bump.
Let us know what happens.