I'm due to start some OU modules in March. Having never studied at the OU before, I'm obviously not going to be an expert but here's my perception of what it will be like.
For a lot of courses, there are online discussions for students to share ideas. You are allocated a local personal tutor and have the option to attend tutorials which involve small groups of students getting together.
You certainly won't be all on your own. The support will be there for you if you choose and want to to use it.