I am so happy to hear that you are going. Please let us know how things go for you there. My experience was really wonderful. It would be nice to get a few different people telling their experiences, even if some are not wonderful.
I hope you can get past the lies. Everything you talk about will be your feelings. Feelings should not be lies, but I know every experience is different. I cannot predict.
You are taking action. No matter what this will help. It cannot hurt the relationship. You have built a life for 17 years. Certainly it is worth a weekend of focused work to avoid throwing it all away!
Good luck. Keep the boat steady till you get there. The other spouse often gets cold feet beforehand. The hardest part is walking in the door. After that it's really both easy and enjoyable.
Feel free to write with questions if you have any. I'm happy to answer.