Hello Matt,
At least we are on the first step to see what may cause the problem of your wife. Probably, she was suppressed her dignity a lot during the time when she was with the previous husband and now she is lucky to find you but she may realise it but in the deep mind. I can understand that she may wan to be adore and be better than any (sorry I hope you know what I mean) by picking off somebody else mistake and eventually she forgets to look at herself that she is not different from those who she criticised. That why it is a bit sad for her. However, now you cannot change her the best is you may thinking about changing and adjusting yourself first. When you feel good and strong ( in term of soul) and that is the time that you will be able to help her. First of all you should feel kind to her and sympathy to her from your sincerity not just think but it should come from your heart. If you can feel that I am sure that you will not feel bad about her. Whenever she does what she used to do, you can comfort her with some gentle speaking with the good wish toward her but if she does not want to listen to you, please do not feel fed up about this. There is a proverb that little drop on the stone will make the stone erode. If you are kind and nice to her everyday, I am sure you will get the same thing back as the law of newton action=reaction (I am Buddhist so in the buddism term call the law of Karma which Karma means the actions) like if you would like people to smile to you, you first have to smile first and if you would like people to hate you, you can go there and hit his head and you will get back the same. If you keep doing this everyday at least you can have free mind that first you will not think your wife behaviour annoy you and you may feel different that you are trying the best to be with no matter how she will be with willingness rather that the word that you have to. Second, evaluate yourself that you may have something that cause this (try to be honest with this). If you may one thing that cause this how you can adjust and adapt yourself for this situation. May be your situation at work is better than her or she feel that you are overpower on her like previous husband and if we can see this problem, it is a good sign to sort out.
Meditation is one of the way to give you peace and clam and when you get this feeling from meditaion you will be able to see the problem more clear like chinese proverb that if you want to see the problem it is better to take one step back to see more clear picture.
Basic and easy way of doing meditation is being with your breating. Because every second we are breathing and we have never realised that we do breathing because the mind is wandering everywhere trying to see and pick lots of problem and if we can make our mind set to something common, it will make you more calm. The way to do it is finding the time at least 10-15 minutes anytime when you feel that you are really down. Close your eyes and watch your breathing focusing at the belly. I use the word watch not control the breathing. When you see (with close eyes) your belly blow and flat called 1, blow and flat called 2, do it until 5 it will be the first set, the second set is do the same as the first set but increase it to 6, do the same and increase it to 7 and 8 and 9. After that from 9 let do the same but drop it to 8 and 7,6 an5 and when it reach 5 go forward to 9 again.
1,2,3,4,5/1,2,3,4,5,6/1,2,3,4,5,6,7/,1,2,3,4,5,6,7,8/1,2,3,4,5,6,7,8,9/
1,2,3,4,5,6,7,8/1,2,3,4,5,6,7/1,2,3,4,5,6/1,2,3,4,5/1,2,3,4,5,6/.......
I hope you understand. You will see when you start to do it there are several things in your head. Lots of stuff that you think think and think for ages but please ignore it and be concentrate on the belly. If you miss out by interrupting by the thought, you have to go remember which stage you re interrupt and restart at 1-5 again if you go forward but if you are interrupt during the doing the counting backward please start at 1-9.
Let's do it first 10 minutes and when the time is over please concentrate and wishing good wish to your wife and transfers all of your kindness to all beings who live in this world with you.
With my experience, I would advice you to do it everyday at least 10-15 minutes and hopefully it can help you more or less. Please keep inform me if you would like or if you do not understand please feel free to let me know.
Good luck