Is this 2.58 out of 4.0? I know that some foreign schools do not use a grading scale based out out of 4.0. In the US, a 2.5 is a B-
You could always take undergrad classes at a local community college to raise your GPA. Take classes relevant to NP like psychology, anatomy, biology, statistics, nutrition, etc. It'll be hard, but maybe you can get that GPA up to a 3.0, which I think is the minimum for most NP programs. NP programs are competitive, so I think this is your best bet.
BTW I was in a similar situation, sort of. My undergrad GPA wasn't so good, and I knew I wanted to go to grad school. I went and got a second degree at Rutgers in psychology. I took 50 credits there but only needed around 35 to finish. I had a 3.9 GPA there and my cumulative GPA is now around 3.4. So it can be done, but it was difficult, and I had to take out loans. If you're very serious about the NP, then this is something you can do. If you decide to just take classes at a community college without being in a degree program, you cannot take out loans. But the classes are much cheaper than Rutgers.