Good luck
You will love it. Give it some time. Give your body time to adjust and get stronger. Give your mind time to unlearn old habits and dismiss pre-conceived notions of what you can do with the bike.
For me, it offers a different experience. I have a full suspension xc bike with gears. I will admit it is easier on my body than my rigid singlespeeds.
And riding technical terrain on a rigid singlespeed bike will beat the snot out of you. For me, it is 2 days a week tops on the rigid 1 speeds.
But the upside? I really don't know how to describe it. A better connection to the trail? perhaps. The simplicity and lightness of the bikes? beautiful.