It sounds like your joint still has some instability. Under the right circumstances or conditions, it gives way or buckles. This may be a sign that you need to continue your rehab program indefinitely. This is especially true if you don't ever plan on having reconstructive surgery.
A home exercise program (HEP) can be very successful in stabilizing the knee when there is an ACL tear but no other ligament, cartilage, or joint injuries. Usually the HEP is a continuation of the exercises done in rehab.
But muscle strengthening, cardiovascular training, agility drills don't always improve knee stability. You may need to carry out perturbation-enhancement exercises. This is a way to restore joint proprioception (sense of position) and quick response to changes in joint position.
Perturbation-enhancement rehab can help the athlete resume pivoting, cutting, and jumping activities without fear of buckling or instability. If you worked with a physical therapist during the first phase of rehab, you may want to contact him or her about adding this key feature to your HEP.