As much as I hate to admit this, I was a person who sabotages at one time. When my husband first started his weight journey 4 years ago, I would cook foods he wouldn't eat and get offended that he wouldn't eat them. After I started to see the results of his efforts, I changed my mindset. It wasn't until I really started my journey that I saw how hard it was for him to say no to me. I have to say no all the time now, and it is fulfilling when I stand up for myself, it is also hard.
I would have a heart to heart with him. Ask him for his support. If you say no cake, you mean no cake. It is not about hurting his feelings, it is about your health and well-being.
Good Luck on your Journey.
“It’s the little details that are vital. Little things make big things happen.” ~John Wooden