I had about four months off over winter - I had pneumonia.
I had a couple of attempts at re-starting during that time, but too early - I couldn't do it, and I got sicker.
However, once I was really over the chest problem, I'd try to start again, but very gently, as if I were just beginning - not going anywhere near the weights that I had been able to lift before.
That was mid-August - now I'm doing better than I ever was before.
I think that what helps is not to think "I've lost all my strength! I can't do what I used to be able to any more!", but "I'm starting [again]! Let's see what I can reach!" - and then measure your progress from there.
The people who have horrific injuries or strokes, and have this attitude, probably do better than those who don't - they count it as a great achievement when they can first stand up, or feed themselves, or something like that.
Anyway, your "hard single" bench of 120kg is far beyond what I can do - 120kg bench is a distant goal that I aspire to!