Meditation

Hi,

For a long time now I’ve been trying meditation to try to lower my anxiety and deal with the effects of ptsd, and also to improve my well being overall. However I have got to the point where I’m beginning to wonder if it can actually help me. I struggle so much to focus and to get my mind to calm and settle. I’m wondering if meditation is particularly difficult for autistic people.

Has anyone on here had much success with meditation? And if so - what kind of meditation practice did you use? I’d really appreciate some advice on this. Part of me feels that I might as well give up with it because all that’s happening now is that I feel like a failure for not benefiting from something that so many other people say is so wonderful. 
Thanks :)