Good if she can go to a professional experienced in survivors of suicide. When you have a heart problem, go to heart specialist. Same thing applies here, but any help is better than no help. I think your mom needs attention rather than be left alone. If you have other family members and or friends that can spend time with her also, all the better.

People who are depressed tend to want to isolate which is possibly something that can get them living in their head and thoughts and not living in the reality that we choose to live in. It sounds a little cold to say it but in my own grieving I had to get to a point of seeing for myself that life goes on somehow even when a loved family member takes their own life or dies of natural causes.

You may find this article has some ideas how to help Coping In The Aftermath of Suicide

Support groups can augment therapy and help until therapist is available. Google search "survivors of suicide support groups" brings up many options.