(((hugs)))
I am very sorry to hear that your mom killed herself.

Getting through such a huge emotional event must have been extremely difficult for you.
You have made it through to having children of your own, and now dealing with their teenage defiance and disrespect. Very common ~ but stressful, that's for sure! Are you working with a pDoc (psychiatrist) as well as a T (therapist) to discuss your thoughts and feelings openly?
Personally, I often struggle with S.I. but it's relieving to be able to discuss these things with my T, without fear of being locked up. Just letting these fantasies and hopes out really helps me ~ instead of continuing to repress. I have 2 children of my own, and I'm very against leaving them while they're so young and dependent. I don't want to mess them up any more than I have already! So, I do remind myself of that fact on tougher days. That can help me.
People do care about you very much. You may not feel that love right now, but that doesn't mean that it doesn't exist. Please don't give up! Call your doctor and get in to see a T asap! Hopefully, the right med combo and dosage is just right around the corner. Try to be patient. You're in my thoughts.