Welcome Isabelle
Hmm...lots of questions, lots of good answers, so I'll try to answer from my experience, strength and Hope, which is as an Alcoholic in Recovery as well as a recovering codependent.
First: How Long Will It Take to Regain My Trust?
For me, it took what it took, your trust may never return, trust, like respect are "earned" qualities, they are like driving, they are privileges, and when they get "taken away" they need to be earned back, if he gets a sponsor who's got any recovery at all this will be pointed out to him, and it doesn't get to be on his "schedule" either, you do what you need to do to take care of yourself.
If he's actually serious about his own recovery, nothing you do can affect it one way or another, recovery is like drinking, we just don't have power over someone else's drinking or recovery, so don't let him play that card, and if he has any questions about that, refer him to me and I'll show him all the relevant pages in the Big Book of AA that refer to marriages and early recovery.
If he is serious about recovery there is a whole section of the book and many passages I call "you'd better clean up yo act up quick if you want to save your marriage and here's how" that doesn't mince words. Just quitting drinking is NOT considered NEARLY enough in AA to save a marriage. As a matter of fact there is a passage about a farmer who comes up out of his cyclone cellar to find his home ruined," looks around, and remarks to his wife, "Don't see anything the matter here, Ma. Ain't it grand the wind stopped blowin'?" (metaphor for his drinking)
This is not considered "acceptable behavior". So you just do what you need to do, he can wait.
OK, Now that we got "him" and "that" out of the way, what I have learned is the focus needs to be on me. The ESH you have gotten already in this thread is spot on.
If he's serious about recovery it will not matter (to his recovery) whether you are away for a while taking care of you.
You didn't Cause it,
You can't Control it.
You can't Cure it.
Did he consider it mean when he was abusing alcohol and all that implies?? He is a grown man that can take care of himself and his own recovery.
How long does it take to regain trust in your partner? As long as you need!
Take whatever time you need, and be gentle on yourself in the meantime, during that time his actions will be all the barometer you need to decide if you'd like to go forward, he'll give you the information over the next few months, so if you take that time to take care of yourself, go to Alanon meetings, get some therapy, you will be prepared whichever way this turns out to move forward and make whatever decision you need to make in a healthy manner.