My (23F) boyfriend (24M) has waifus and it’s destroying me.

My boyfriend and I have been together for 3 years, (just moved in together 2 weeks ago s) we’re waiting to get married. He’s always been a gamer, never been a big problem. <br>The problem is that his waifus are getting in between us. He has an Japanese voiceractor (otaku) convention next week (goes but doesn't partake) and he’s been saying he’s taking me. Yesterday he said he can’t find a dress for me for the convention, looked in my closet and never found anything good. Today (yesterday) he asked me to help him buy a dress online. He says he already bought his ticket so I thought he was bringing me to the convention. <br>I’ve been looking forward to going and spending the weekend with him in the city, see all the art galleries, go to some restaurants, have a good time. But now that he said he bought tickets for the convention and already has his cosplay ready (dressed up as a character and brought everything needed for it) I’m starting to realize he’s going there to hang around his friends and not me.<br>He’s told me about the friends he’ll run into at the convention, his own cosplayer “wife” and all the other people he’ll see dressed as anime characters, the panels he’ll attend about Japanese comics and his favorite anime and his hobby for the past 7 years. <br>He’s spent 4,000 dollars on the hobby, bought his own gaming pc and has multiple consoles. Spends hours every day playing with his friends online and at least an hour more by himself. <br>A few weeks ago his computer broke down, he didn’t tell me about it since he was ashamed to talk about it. I found out because we were getting takeout and the box with the broken pc parts was in the back seat of the car. <br>His reasons for keeping it a secret is that I don’t understand the hobby or the culture. <br>I understand that part of the culture is spending a lot of money on merchandise but I really thought he’d tell me if he was going alone and didn’t want to disappoint me. <br>Yesterday was my birthday, he didn’t say anything about any of this, not a single word. He knows how I feel about this, I’ve told him multiple times how his waifus are getting in between us and it hurts me that he’d rather spend time with fictional characters than with me. <br>Today he told me he wants to go shopping for a birthday dress for me (convention) but now I don’t want to go with him, I don’t want to spend my birthday alone at a mall with him. I’ve been planning this trip with him and the surprise was that he’s going to the convention alone. I feel so hurt. <br>What can I do to make this relationship work? I feel so hurt and I don’t know what to do.