I am unable to regulate my emotions and I ruin everything. Please help

My biggest challenge as an autistic woman is regulating my emotions.

I've always been highly sensitive and tend to break down during the worst moments, ranging from work to family events. My strong reactions tends to bring everyone in a horrible mood and I ruin everything.

As a random example, my mother decided to photograph the family, including me. For context, I have body image issues. Although I've been getting better, this incident has broke me down. As I instantly demanded for the phone, I zoomed in to check every detail of my body and I looked disgusting. This made me want to self isolate and minutes later, my mum checked on me and said I could have 5-10 minutes to snap out of it, considering guests are around and she didn't want me to ruin the event. During my 10 minutes, I continued to cry, started banging my fists against my head and screamed. I assumed since everyone was outside, I could scream in peace. However, one of the windows upstairs was opened and everyone, including the neighbours heard me. This ruined the night for everyone.

I have no idea how my family has forgiven me so many times for letting my intense meltdowns ruin special events. I don't deserve their forgiveness and they don't deserve me as a daughter.

I am unable to get therapy, but how can I hide my emotions so then I can finally stop ruining everything. Please help.