Hi @dangerousmusic. Thanks for being part of GoDaddy Community! There are a few things you can check in this situation:
Add an SPF record to your domain if you don't have one. Mail sent from any of our email servers should have the followingSPF record: v=spf1 include:secureserver.net –all. Since you're also using Gmail to send mail, you'll need an SPF record for their servers as well.
Don't use a generic subject. If your email form sends with a subject like "new message" it might be blocked as spam. Changing this to something unique may help.
If these suggestions don't help and you're not getting a rejection notice from Gmail, you may want to reach out to their support to see if they can help.
JesseW - GoDaddy | Community Manager | 24/7 support available at x.co/247support | Remember to choose a solution and give kudos.