Time can certainly help put things into perspective. But if nothing has changed in the interval than there is no reason to trust him to not break a boundary again. After a breach in trust, I think that trust has to be earned - it cannot be as freely given as it was before the breach (at least for me).
First you have to be able to forgive the person, before you can ever start to trust them. Then they have to be a.) genuinely aware of and remorseful for what it was that they did b.) self-aware of the factors that contributed to the decision to behave in an untrustworthy way c.) make changes in their life and attitudes that ensure that they will never put themselves in a position to betray your trust again. A superficial "I'm sorry, I won't do it again, trust me." - doesn't cut it.
You have to show me, not tell me, that you have done the work and made the changes, in yourself, that make you worthy of being trusted. I can love you and I can forgive you...that doesn't mean I will trust you, until you show me that I can.
Me: poly bi female, in an "open-but-not-looking" Vee-plus with -
MrS: hetero polyflexible male, live-in husband (21+ yrs)
Dude: hetero poly male, live-in boyfriend (3+ yrs) and MrS's best friend
Lotus: poly bi female, "it's complicated" relationships with Dude/JaneQ/MrS (1+ years)
TT: poly bi male, married to Lotus, FB with JaneQ
VV and MsJ: bi-women with male primaries, LTR LDR FWBs to JaneQ
My poly blogs here:
The Journey of JaneQSmythe
The Notebook of JaneQSmythe