You did not say at what point in your cycle the u/s was done nor your age or menstrual regularity or irregularity. But a thickness up to 1.6 is considered normal in the second half of your cycle so you are not too much over that. I have actually heard of women with a thickness over 3.0 whose biopsies were normal. And if you are in perimenopause, the lining can get overly thick due to lack of ovulations. But in most cases, the body does a good job of clearing it all out over time before anything serious happens.
If the biopsy would happen to show hyperplasia, that is usually curable with hormonal (progestin) therapy.
Let us know what you find out and try to stay calm.
I also had 2 cysts removed by surgeries & now my uterus is thick & I have another cyst, I just wanna say that u shouldn't over think about it & everything is going be fine, don't worry :)