cmarch,
I'm so sorry to hear your story, but so glad you found this site.
The are many resources in the Healing Library that is pinned at the top of the Just Found Out forum. That's a great place to start.
It is totally normal to feel, hurt, overwhelmed, and confused at this time.
Prioritize taking care of yourself emotionally, physically, psychologically. Eat, rest/sleep, exercise and hydrate. See your doctor if you are struggling with any of these basics to get the support you need to take care of yourself.
...should I accept that I played a big part in what happened and just move on?
I say this gently and respectfully: while it's healthy and helpful that you own how you contributed to the dynamics in the marriage, she made choices. Even in the depths of her pain, she made choices. And she could have made other choices--to speak more openly with you about her own pain and despair, to seek individual counseling, to seek marriage counseling, to separate from you, or to outright leave. You are asking the questions you are at the end of your post because of the choices she made.
Can my marriage be saved?
First, nothing has to be decided now. Give yourself some time.
Marriages can be repaired after betrayal, but it is hard, hard work. Both partners must be committed to:
Honesty with themselves and their partner
Prioritizing open and honest communication with each other in an ongoing way
Working on their own issues and personal healing to become a safe, trustworthy, and supportive partner (for many people individual counseling is helpful for this)
Many will caution you not to rush into marriage counseling too quickly, but rather to prioritize individual counseling and healing first. This is sound advice.
Too many marriage counselors are not well equipped to deal with the trauma of betrayal and will gloss over the personal responsibility the wayward spouse needs to own and the true healing that needs to take place for both partners to be safe in the relationship.
If you choose to stay for now, expect it to feel like 1 step forward and 2-5 steps back at times. This is a time of turmoil. Be gentle with yourself.
Is it worth it?
Only you can determine this. Give yourself time to decide.
You have many choices and any of them are valid and completely okay to move forward with:
You can separate for now--either within the same house or outside of the same house. You can use this time to heal/work on yourselves and make no permanent decisions.
You can stay and begin healing/working on yourselves and your relationship.
You begin divorce proceedings and begin moving forward with your own healing.
Many others will be offering their support and advice. Take it all in and weigh it carefully, but accept what works best for you.
Sending you strength!