relationship advice

the other day my boyfriend and i were scrolling through his phone notes and there was one from a year ago with his exes name with a date of when they’d want to get married — I don’t care that it’s an old note, but he’s always told me the entire time we’ve been together that he only wanted to marry me and im the only girl he’s ever pictured that with. it just hurts that i was honest when i saw futures with people and i let him know but he had me feeling he’s only felt a certain way once with only me but apparently not. just want advice on what to do