If your spouse's weight gain has upset you, you may ultimately decide that his weight is not up to you and that you need to get over it. The only thing in your control is how you respond. Hopefully, you can learn to accept your overweight spouse for who he is.
Come to terms with the fact that your spouse is gaining weight and that there's nothing you can do about it. It's truly not up to you whether she gains weight. It's up to your spouse. If you can realize that the issue is not something you can fix, you can get over it a lot faster.
Understand why your spouse is gaining weight. Gaining weight usually corresponds to social activities and a mental issues. Perhaps your spouse lost his job or is coping with a death in the family. Knowing the reason for the weight gain can help you determine if and when it will potentially reverse itself.
Find out if your spouse plans to go on a diet or add more exercise to the daily routine. If you can acquire information about whether there is a diet in the works, it can help you get over the weight gain more quickly.
Support your spouse as she deals with the issues that are causing the weight gain. Though these problems can be very sensitive, your spouse should be able trust you to help her work through it in a non-judgmental way.
Find other activities to keep your mind off the weight gain. If you cannot get over the fact that your spouse is overweight, it will cause problems in your marriage. Find a hobby that either involves your spouse or doesn't change the amount of time you spend with your spouse. Your spouse may be highly sensitive about the weight gain, and may not be able to handle losing more time with you.