He’s moving

My boyfriend (19) and I (18) have been together on and off (majority on) for the last 5 months and we love each other but he does have troubles with his mental health and the town we live in doesn’t do a lot to help the case, so he is moving an hour away. We have talked about how we’re not sure what will happen with us because we basically live together and spend every day together and we’re each other’s best friends but it worries me. Any suggestions on how to make the “long distance” relationship stronger and at least last a couple months until the roads are in better conditions and I can drive to see him more? Also any suggestions on how to deal with and help with his seasonal depression?