I'm probably exercise phobic too. I'm a big girl. I have tried and tried and tried to get into walking, because it's easy. Because it's free. It's accessable. Doesn't need a team. Can be solo or with friends. And I absolutely hate it.
I cannot make myself go for a walk for the sake of a walk at all. I am a little agoraphobic which doesn't help but ugh. It is not my option. I also have some hip issues which limits how far I can comfortably walk.
In the spring I contacted a local female personal trainer. I now go to the gym once a week with her. I was a mess my first session but have improved dramatically. The warm up on the treadmill is predictably the worst bit for me and angers my hip but nothing else bothers it. I do squats, I lift weights. I'm achieving much more than I ever felt capable of and what's more, I actually enjoy it and miss it when I can't go!
I Def think it's about finding the right thing for you, and I just want to add that if walking isn't the thing, it's ok