Extreme shame about a fetish

Hi there, I'm a 23 year old male and lately I've been having extreme anxiety and panic attacks about a fetish that I have always had. Basically, my fetish revolves around women's panties. They turn me on more than anything and always have ever since I was a kid. When I was younger, I sometimes went through my sister, mom's, or my friends mom's underwear drawer when I was at their place alone and would sometimes masturbate with the panties. I knew it was wrong at the time to do and lately I've been feeling extremely guilty about what I've done and feel like I deserve to die. I feel like a pervert scum that doesn't deserve to live. In the past few years ive talked to a sexual therapist about the fetish and they said there's nothing wrong with having a fetish as long as it is contained. I've found online that there are women who will sell you their underwear and have managed to have this be my only outlet for the fetish if I'm particular aroused . I just can't help but feel extremely anxious about the things I did when I was younger and feel like I deserve to die. Many times it's all I can think about and have insomnia, etc worrying about how I deeply hurt other people when I was younger and don't deserve to live