Is 1 month to soon to start seeing someone else after a 3 year relationship?

Me and my ex were together for 3 years. When we got together i had a 1 year old and we ended up having a baby that is now 1yr 7months. Our relationship used to be great in the first year but then he started leaving me home alone all the time to hang with his friends and sometimes come home late at night like 4am or even later. My brother committed suicide 2 years ago and i found him and after that the ptsd caused me to be afraid of the dark and scared to walk into rooms, but he was never there for me during that time. He apologizes but it’s something i think i could never forgive him for. My mom gave me house that i can raise my babies in and he moved in with me and my mom charged him $100 a week and he never paid, he also never paid the bills until things got cut off. I don’t work, i stay home with the kids, and I’m also a college student. I’m currently 24 years old as is he. He’s a mechanic makes $1000+ a week but i never know what his money goes to because bills and rent are never paid. He’s wrecked 2 of my cars and hasn’t fixed them so i eventually got to where i was just going through life like “whatever”. He broke up with me a month ago because he says that i act like i don’t give af about him and like i don’t love him but i do, i plead my case then he proceeds to tell me that he’s stopped caring and that he was gonna come home from work that day and pack his things and move out to his sisters house with her and her roommates and pay rent there. So he left. I feel like our relationship was over a year ago because things never got any better even after we’d talk about the things we need led to work on together. I’ve been so happy and stress free since he’s been gone it’s ridiculous, anyways, This guy that i used to date back in 2014 (that i really cared for) messaged me and we have been talking and have seen each other 2 times this past week and things with him seem to good to be true but it’s like we picked up right where we left off. He has a good job, he is very good with his money, he’s sweet, funny, and ,to me, everything you could possibly want in a guy. My question is, is it to soon to start seeing someone else? Sorry for the long post and i hope it makes sense.