In addition to suppressive therapy, what else should a person do to reduce frequent hsv 2 outbreaks? what can be done to strengthen the immune system?

RELAX: Relaxation strategies to reduce stress. Adequate sleep, regular exercise, and healthy diet. If outbreaks are labialis (face/lips), then avoid prolonged UV exposure (sunlight).

Sorry, not much: Unfortunately, no proved methods. Maintaining health (rest, exercise, balanced diet) is always good. Avoid things that seem to trigger oubreaks, but clear triggers are rare for genital HSV2; outbreaks are random and don't indicate immune system weakness. Suppressive therapy is the only thing that works reliably. Frequent "outbreaks" while on suppression usually turn out to not be herpes.