I liked your title "My boyfriend is a runner." I have a suspicion your anger is justified. However, your response has to always treat him with dignity and respect. You can tell him "I feel ... when you don't tell me things, or when you say things that aren't true." You can say "I feel frustrated when you don't answer me." After that you have to make a decision based on the information you have. You deserve to treat yourself gently, to not have to go to an extreme to make your relationship work. Sometimes, you can walk away to save yourself, and still love someone. This is advice I am giving myself for my next relationship.