Don't be in denial about it. Your mom may(well she just will) be thinking about it a lot. She'll have some times when she needs to talk to someone about it. Be supportive and listen when you need to. If you see her down or a little quiet, bring it up. Ask her if she wants to talk about it. How is she mentally doing... that's where you can help. I don't mean to be pie in the sky about it, but talk about it. There will be times when she's just mad or sad or just plain pissed off. Your job is to just let her get it out and give her a big hug when she's done.