I feel like I’m going to fall apart and I’ve still got 2 kids I’m parenting, how do I keep it together for them?

i feel lost sad and broken like i have two kids and im a single mom so when i got pregnat with this son i didnt or couldnt have it my aunt cant have babies i thought it the purfet solution but now all i feel is horible its been a week and even though i have nothing to give this baby i cant stand the fact that hes not with me it made me feel better when i went and looked at the nursery and all she could give him it made me feel better.But short lived iive got to go back to texas now and i feel like im going to fall apart and ive still got 2 kids how do i keep it together for them?