When a couple has broken off their relationships because one of them has trust issues, the other partner might find someone quickly. It will be a sign to the person unable to overcome their emotional boundaries that they were never truly loved, but it might not be true. The other person might have been deeply in love with them at one time, but the erosion of their relationship caused the bonds to loosen. They are able to find someone quickly because they have been prepared for the breakup for a long time. It can be difficult to accept, but it is the fault of the person who chose not to resolve their issues.
Looking from the outside into another relationship is often misleading, but seeing a former partner happy with someone else does give a clue to how they really feel. The person who was unjustly accused will find there is freedom with a new partner, and their joy in being able to share their life with another person will be reflected in their smile. Contentment might have been something they sought for a long time, and they have finally found it.
The person who has trust issues must learn to get past their relationship, so they need to do it by working to resolve the feelings that put them into that situation. They will never be truly happy with another person if they refuse to look at their own behavior, and they will drift through relationships without any real connection.
It can be difficult when a person has difficulty trusting any partner, and they will never experience the true happiness that can be theirs in a good relationship. Finding the courage to move past what has happened before can give them an opportunity to find happiness, and they might finally find the person just right for them.