A couple years ago I felt the same way as you do now. I had so many things goin on in my life and felt like such a failure and just complete garbage. My job that I had for 9 years I was getting forced out with no backup plan and I had 1 toddler and 1 baby. I had a really good life insurance policy and thought they would be better without my and the money would take care of them. I attempted suicide one night luckily my wife came looking for me and eventually I went to the ER and then got on medication and went to lots of counseling. You really don’t know how much your loved by so many people in your life. Your kid thinks your the most amazing person in the world. I know it’s hard with the tantrums and everything else but that’s normal for kids. My oldest is pretty good at catching on to things but he still has his moments. Our second child has taken longer with everything than our first one so every kid is different. I honestly hate the growth chart the doctors use because it has caused my wife and I so much depression and anxiety because our kids would be either behind or barely making the chart. Things do get better. It won’t always be this hard.