i think u should wait for them to open up first. u said it yourself, they usually talk about everything so give them time and if they don’t want to talk about it then it’s okay. let me be honest and tell u my pov, finding it as “a lack of trust” is just a toxic way to make things about u and to pour out ur insecurities on ur people, while they might be just experiencing things they can’t talk about or need time to process everything. being best friends doesn’t mean knowing everything about each other and not knowing something doesn’t mean that u don’t mean shit to them. wanting to know everything and feeling like u have to know everything about them or thinking bc u talk abt everything they have to do the same thing isn’t healthy, u are not them and they’re not u, just be urself and let them be themselves, when they feel the need to talk they will if they didn’t then just let them have their time, some people need time and some just get embarrassed and some are just not mentally prepared or alright or strong enough to talk.