Should I seek a diagnosis or not?

Over the last couple of years I've come to realise that it is very likely that I am autistic/aspergers. In every online test I take I score very highly. My son is autistic and so as I have learnt more about autism I've felt that it would explain a lot of how I am and feel. 

I am now considering seeking a diagnosis but I am unsure whether to go for it and was hoping that some of you may be able to tell me what the benefits might be.

I'm a 38 year old woman, married with 2 young children. I think I am very good at masking outside of home but it takes a huge amount of effort. At home I'm constantly on edge, I wonder if I'm trying not to mask but then being judged for it so not sure who to be. I left work to care for my son but I don't feel I could return because I'm afraid of repeating some horrible experiences I have had there. I'm exhausted and struggling with anxiety, and the fight to get my son the support he needs is taking its toll on me because of all the meetings and phone calls. I am, though, worried that the people in my life who I have difficult relationships with could use a diagnosis to say that all of the problems are just because I'm autistic and not due to any bad behaviour on their part. 

Do you think a diagnosis might help me? If so, in what ways? 

Thank you for taking the time to read this far.