Wishes about the present
wish / if only + past subjunctive
This pattern is used to express wishes or regrets about the present:
I wish I lived nearer. Then we could meet more often. (I'm sorry that I don't live nearer)
Cathy wishes she had blond hair. (Cathy is sorry that she doesn't have blond hair)
Instead of the past subjunctive, we can use could + infinitive:
You're brilliant. I wish I could play the guitar like you. (I'm sorry that I can't play the guitar like you)