Households in ecologically sensitive and geographically peripheral areas face environmental, economic and institutional constraints that may jointly weaken livelihood resilience. Using 1851 valid household questionnaires from Guangxi, China, this study examines conditional associations between perceived environmental constraints and livelihood resilience; 419 observations from the eight China–Viet Nam land-border counties form a focal geographic stratum. Formative indices measure perceived environmental constraint, green living capacity, adaptive capital, livelihood-strategy diversification and livelihood resilience, while infrastructure and digital access are treated as contextual controls. County-fixed-effect path models with HC3 intervals, county-stratified bootstrap products, subgroup contrasts and a leakage-free elastic-net classifier are combined in a complementary explanatory–predictive design. Perceived environmental constraint is negatively associated with resilience (beta = −0.121, 95% CI [−0.169, −0.073]). The adaptive-capital indirect association is −0.050 (5000-replicate 95% CI [−0.065, −0.036]); the green living and diversification products include zero. The preferred classifier achieves test AUC 0.735 (95% CI [0.693, 0.777]). The findings identify robust conditional associations, not causal mediation or disaster effects, and support coordinated ecological governance, service access and household capability support.