Yes, it is a rollercoaster ride and as a rider, you determine when you want to step off of it.
There is no telling why he tends to tag along on outings w/your son. It could be any number of reasons: 1) it's a habit formed per-crisis and he tends continuing it; 2) he considers his son his best bud because his son doesn't judge or criticize him for what he's doing; 3) he's bored and wants to do things; and 4) it's a good way to keep tabs on you and what you are doing w/your life. It could be any or all of the above, but it's not worth trying to over analyze. Be grateful he wants to spend time w/his son. Some don't.
He may not wish to tell the OW about the job interview until he is offered the job. If he gets the job, he may want to keep it as a surprise and dangle it as a carrot for the OW to decide to go w/him. Again, no telling why he's keeping it a secret.
Don't try to over analyze his every move of word because it will drive you crazy. They change on a dime and give you 2 cents change. There's no rhyme or reason for what they do. Tomorrow things could be totally different and that's why it's important to keep the focus on you and your family.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
