Help pls :(

My sons father and I have been together almost 6 years. We split for a year & decided to pick back up on things. Lately he’s been “super busy” to the point he can’t even spend time with his son. We talk at night. That’s it. Call him throughout the day bc my son wants to talk to him & after about 5 minutes he rushes him off the phone. Someone texted me about a week ago from a text free number talking about they were messing with him & there was another girl (a girl I knew he was messing with before we decided to pick back up). He gave me a bs story about them fighting & she tried to kill him or her family was racist OR something about her baby’s dad) There has been a thought in the back of my head that I really can’t shake. He always tells me he was sleep or handling stuff. When we talk at night it’s for about 30 minutes to an hour then all of a sudden he’s going to bed. Nothing really adds up anymore. Idk if it’s because I really want something to be wrong or something really is wrong. There’s really so many things wrong in our relationship and I know we shouldn’t be together. (He constantly calls me lazy because I chose to stay home with our child to get him ready for school (k4). I still have money coming in though. When I bring up how I feel about him not spending time with us he tries to guilt trip me. Or there’s something wrong with his car) we use to have family day literally ONE day out the week but that stopped because he doesn’t want to drive around. I’ve offered to drive or taking our son to parks and stuff. Let him wear himself out. I’ve offered to pay for everything. He just doesn’t want to spend time at this point. And I’ve learned to be okay with it now. It’s overwhelming and sad bc what do I tell our child. My sweet boy loves his dad but I’m honestly ready to throw in the towel and move away.