MNS, I am so sorry for what you are going through. There are so many people here who know all too well how you feel - this is the best place you can be.
You cannot expect to get it together in one day, MNS. It has only been 6.5 weeks since my BD and I am still on a major roller coaster every day. I am not sure there is a day that has gone by that I have not cried. Sometimes I just get choked up and manage to stuff it down and concentrate on something more positive, but a lot of the time, I cry my eyes out. During those times, I allow myself to cry, but I remind myself that later, I will be feeling much better - this helps me to drop the gloom and doom and hopelessness and accept that it is all part of the process. Grieving and healing are not linear. You will not necessarily feel a little better each day, but you will see an overall trend of healing.
The intellectual understanding of where you need to go is easier than actually doing it. HOW am I supposed to pretend I am happy when I feel awful? HOW am I supposed to go enjoy other activities when all I can think of is how my world is falling apart? The answer is - you just DO IT. The first few times (maybe the first dozen times), yes, you might spend the whole time hating it and being sad. But do it anyway. Keep doing it. Soon you will start to see that you can find joy (and better yet, distraction! Even if for a short time) in things. Do not isolate yourself. Talk to people. When you find that someone is not supportive, do not talk to that person. I am not going to judge your mother, but it sounds like she is not someone who is going to be good for you to talk to. Reach out to friends, acquaintances, family - even people you haven't talked to in years. You will be amazed at who is really there for you.
Please exercise. Do something that is high impact. Run. Take a kickboxing class. Play basketball or tennis. It helps. A LOT. Look at yourself and your shortcomings. Don't beat yourself up about them. Figure out which ones you can and should change, and work on that. Know that you will be a better person. Behave with dignity and know that in time, you will look back at this, and no matter how it turns out, you will be proud of the way you handled it.
Hang in there, and keep posting! You are stronger than you think - you've got this!!
me: 44 XH: 42 M 11 years D10 and S8 Bomb drop 9/27/13 D final 7/1/14