AITAH for telling my girlfriend her best friend has 2 years to find someone or we're moving ahead without that condition?

So me (28M) and my girlfriend (28F) have been together for 3 years now and i recently brought up the marriage and kids talk. My reason is pretty simple, i want to be fit and active while my kids are growing up. Like if we have kids at 30 ill be 48 when they turn 18 which still feels decent enough to actually be involved and active in their lives. So i wanted to start planning ahead. She said she also wants to get married and have kids but she had one condition. She wants to get married around the same time as her best friend. Not the same event necessarily just the same season or timeframe. Honestly i found it cute at first. Here's where it gets complicated. I actually know her best friend personally and she is genuinely terrible at relationships, never lasted more than 6 months with anyone and is currently single. But the bigger issue is her best friend doesn't even want to get married. So my girlfriend's whole plan is to first convince her that she wants marriage, then find her a guy, then hope that guy proposes, then coordinate weddings. I told her i don't mind waiting but i'm not comfortable with our future basically being in someone else's hands. She got upset saying i don't respect the friendship. So i said fine, 2 years, if things fall into place great but i can't wait forever with no end in sight. That got her even more riled up. AITA for putting a timeframe on this? EDIT: so after reading through all the comments i decided to reach out to her best friend and told her everything. and honestly her friend found the whole thing just as ridiculous as you guys did and immediately went and talked to my girlfriend trying to knock some sense into her. now my girlfriend is mad at both of us lmaooo. but hey at least her friend and i are on the same page. will update if anything changes.