I just lost my GF of over a year. It's rough cuz some of it was my fault. I gotta add something to what everybody else has said though...
Getting into old hobbies will definitely help you to ease some of the pain and get your mind off onto more constructive things. It will also help keep you from making decisions based solely on emotions rather then reason right now. All these guys are right, give her some space and let time heal you both. I wouldn't try to manipulate her by trying to get her to see you out with peeps havin' fun and all that, becuz that's playing games with another persons emotions. Eventually they will figure that out, and believe me, women have no respect for guys who play games with their emotions. Just be real and be sincere, she'll be more drawn to that then anything.
Also, and more importantly... I don't know how many times I have made the statement in my life that "I don't know how I am going to go on without them." I feel you friend. I can relate, but I have found an answer. It's something I have known for years, but had to learn again recently.
When we hang all our happiness and our fulfillment in life on another person, we put expectations on them that no human being can meet. I looked to the relationships in my life to meet all my emotional needs for years. I was miserable, cuz no woman could measure up, they would all fail at one point or another. It's not cuz they're so bad, but becuz they're only human (just like us). We were designed and created by God, by Jesus Christ. He and He alone can understand us completely, has promised to "never leave us or forsake us" and is the only one who can meet all of our needs. I started a relationship with Him years ago and it has made all the difference. He has taught me how to love others without expecting them to meet all my needs. We are all designed to need love and acceptance, but only God is able to do that unconditionally without fail. Now the relationships that I am in, I can enjoy them for who they are becuz my relationship with Christ is fulfilling me. Not to mention He is constantly challenging me and stretching me to love others more. Because of that, I have learned how to treat a woman right. I know this becuz my GF was constantly complimenting me on that. Unfortunately I got my eyes off Christ, wasn't spending as much time with Him and began to lean more heavily on my GF. She is going thru a great deal right now, and the extra load I was putting on her was more then she could take. Now we're apart and I don't know if we'll get back together. It's not the end of the world becuz Jesus is in it with me, not condemning me, but directing me and holding me up.
I want to encourage you, relationships are wonderful, but your needs are greater then any person, female or not, to meet completely. If you don't have an active day by day relationship with Jesus Christ... like you would with any person, then your tank is empty, your reservoir is dry and you're going to be putting your emotional thirst on every one you get close to. If you don't know Jesus and you want to you can call 1-888-NEEDHIM. They can tell you how. If you already know Him, then sit down with Him and just get real, be honest, pour out your guts man. He'll meet you where you're at! I know to some this might be preaching...LOL! And it is, but only becuz I've lived it and I know it works. He is real and He makes a real difference.
I'll be praying for you friend. God bless you and take care.