I do a mix of running indoors and outdoors. For one thing, I’ve found that it helps me to have a friend to run with. It is intimidating if they’re more physically fit than you, so try to find someone on the same fitness page. Running should be about enjoying yourself and not about stress. Chris and I canNOT run together, because I am way too competitive and, like you, get upset when he’s easily running beside me and I’m puffing away like a train engine.