I am currently at my worst mental state when it comes to attending to big social events right now. Last year, my friend planned his wedding for this year in august and I told him at that time that I will be there too. But recently I got so much stuff going on in my life that I am not ready for such a thing. He knows already that I am not doing well especially since I havent been active at all in our friend group where both of us are in and he asks me from time to time how my day was and if I feel better. I told him 2 weeks ago that I look forward to coming to his wedding atleast and he told me to register for the wedding until the end of march via a link. But now that I am thinking about it, with how its going currently, I rather not come in my state and want to decline. It hurts just thinking about it since he is my friend but I also feel like I would not feel well there. I have been thinking if I should maybe just register and decide later if I should attend or not for the possibility if I want to appear later. The issue is, I really have no idea if I can attend to his wedding or not and dont want him to make preparations for me only to get declined in the end. What should I do or say to him right now?