Anyone else autistic and can never decide if you are welcome somewhere?

My kids and I hardly ever get invited anywhere but when we do I move heaven and earth to be there. I worry if I decline for legitimate reasons I may not get invited again. When I do go though I feel lonely and alone in a crowd. People make empty promises about play dates they never plan on having with my kids, I'm often on the sidelines because one of my twins is disabled and cannot participate in a lot of things. I feel judged because it's extremely hard to make sure my daughter behaves well and deal with my sons medical needs. Sometimes she rips books, doesn't share, trys to run off. I'm not always in good control because it's hard when you need help but don't have any. I feel less than because other moms have well behaved kids that require less supervision. They can watch from afar and have the snack provided or drink a coffee. Usually I cannot eat or drink. I feel like I get a pity invite once or twice a year when I can hear from the other ladies chatting they get together as a group regularly when I haven't been invited. I've made dumb excuses and hired a teenager from down the street to come help with the lie that I had to watch my niece so I brought her along so I can participate with having a visit. I don't know if I should even be accepting invites out. It makes me feel really sad sometimes to know I've been excluded regularly probably because my daughter doesn't always behave well and my son isn't very fun. Maybe they don't like me either idk. Lately I've been paying another mom to let my kids come over and play with her child but that just seems pathetic to say out loud. I don't know what to do. There are no groups for disabled children my sons age (he's 3), he isn't welcome in baby groups anymore. He can't participate in any playgroups at family centre's that are age appropriate either because they are very active or just mentally beyond his current abilities. We do go to the ymca and use childminding but they only will keep him there if they don't have many kids because he has high needs. When we go there I'm alone and wait till the 90 mins are up. I've been trying on here for 3 years and people say they want to get together and then will not commit to a.day. I'm just feeling so lonely