While I'm afraid to make any big change, I'm unhappy in my marriage both mentally and emotionally.
What types of changes are you referencing?
I want to work on issues that are coming up within our relationship.
If you think there are issues in your marriage you should try to resolve them with your partner. You don't need to be afraid of making any changes.
I've tried talking to her but she didn't care much.
Being stuck in a bad situation is not good for anyone and I think you should try to talk to your wife again. It's good you are putting forth effort and can recognize that things need to change for the sake of your own happiness and probably hers as well.