Help with my mom's depression/anxiety?

i am 14, my mom is always feeling bad and almost always has a headache. my dad ped away in 2000 of a suicide. now she has a new boyfriend that she loves alot. my brother misbehaves alot and i think that that is part of the problem. anything that could possibly help i would be thankful for. she took an antidepressent one time and that made her have suicidal thoughts so her dad immedietly threw them away. What do you think could possibly be causing her headaches every single day of her life?