Welcome to the forum, Jesse. You've come to the right place to get support as you approach your knee surgery. You are right....it IS a big deal. But.....it is a decision that will make a major improvement in your life. Once you get into recovery, you will begin to get "you" back because you'll be able to move without knee pain.
The first week or two are probably the worst after surgery. I won't lie to you. There can be some pretty significant pain. But today's pain meds are so good, if you stay on schedule taking them, the discomfort is really minimized.
And it's a funny thing....the pain is so different from that bone on bone knee pain. It's hard to describe unless you have been through it, but it's somehow a "healing" type of hurt. You just know it's going to get better and soon! And - BONUS - your new knee is soooo stable!! For me, that was the biggest thrill after surgery. My first step in the hospital the day after surgery I could tell that knee was firm. Glorious!!!
So try not to worry. You have already passed the most difficult part - making the decision to HAVE surgery and getting it scheduled. Time will take care of the rest and soon you'll be a new person. In the meantime, post any time you feel like it. We'll always be here to provide support and address any concerns you might have.