I was always had issues with afternoons, not evenings. I trace that behavior back to being a "latchkey child." When I got home from school, I wasn't allowed out of the house, there was nothing to do but watch TV, read and eat. I always get hungry/snacky between 2-5 at work but I am very rarely hungry after dinner.
Maybe some of the things I do to defuse my afternoon hunger cravings would work for you after 6:00.
1. Plan your meals. I always plan to have at least 2 healthy snacks in the afternoon, sometimes 3. Usually, it's fruit and cut up veggies (carrots, grape tomatoes, sugar snap peas and pepper strips). I buy snacks on Sunday and pack my lunches/snacks for all 5 work days on Sunday, so they are ready to go. If I don't eat them, they will go bad and I hate to throw away bad produce (waste of money). Make sure you have a healthy dinner/after dinner snack ready.
2. Stay busy. I deliberately schedule meetings in the afternoon. You could work on hobbies or write letters/emails to friends/family.
3. Junk proof your space. I keep healthy standby snacks at work (like dried fruit) and absolutely no junk. I never keep cash/coins on me so I can't hit the vending machines.
4. Sip herbal tea. I am a tea fanatic, in the afternoons I drink at least 2 cups of herbal tea. I love Stash Blueberry - it's naturally sweet. This keeps my hand moving something to my mouth, fulfilling the desire to be eating (like how smokers chew toothpicks to fulfill the physical craving).
5. Brush your teeth. I hate eating with a minty mouth. If I am snacky but not really hungry, I will sometimes brush my teeth - I never want to eat right afterwards.
6. Make sure you are eating enough throughout the day. Lots of people are "good" and "careful" during the day and then lose it at night. In my experience (when that happened to me in the past) I really wasn't eating enough during the day, I was overly restrictive. It's no wonder I ate outside of my control - the body wants to LIVE!
SIX YEARS at maintenance weight!
My very long weight loss story
"I saw an angel in the marble and I chiseled until I set it free."