In being diagnosed with a serious and/or chronic illness, it's initially very dependant on your attitude as to how you deal with it. After this initial shock dies down you have to actively make a choice; to survive and thrive or just survive.
I've seen both sides of this particular coin in my short experience in living with Crohn's Disease. I've even been through both of them myself.
I go through ups and downs with my disease, physically and mentally, on a very regular basis. This unfortunately isn't uncommon and can be incredibly difficult to cope with. Feeling down when in consistent pain or in being forced to spending prolonged or regular periods of time in hospital is natural; you have to make allowances for this and try to be kind to yourself. On the other hand ensure that when you are well you allow yourself to 'forget' about your illness if you can, and enjoy your life to its fullest.
It can be upsetting when you encounter people who seemingly choose to focus on nothing but the negative. I've learned to steer clear of these attitudes wherever possible, whether it be in my personal life or in the realms of social networking. If someone's constant negativity starts to wear you down or have an affect on your own mental health, then show them the metaphorical door. This isn't always as easy as hitting an 'un-friend' or 'un-follow' button. If the person is closer to you than just a tiny face-box on a screen, then try to talk to them; explain you feel they always look on the dark side of life and might be better suited to trying to keep things positive. If this doesn't work first time, persevere if you feel they are worth the effort. If they still choose to put their energy into misery and bitterness, slowly phase them out. That might sound harsh, but it's really not, it's another tool for helping maintain good mental health.
You are already going through a consistently difficult time, you need people around you who care, want to help in any way and who make you feel life is truly worth living. You must of course give the same back in return to your loved ones. Let them see you are thriving despite your condition. You have no idea the difference it makes to your own outlook and to the way others see you.
Bitterness and anger at how unfair the hand you've been dealt is, will eat you up. It will impact on your health and on everyone around you. Remember that everyone faces trials in their lives, you are not unique in your pain. Don't play the martyr, if you need help then simply ask for it. You'll be surprised how accommodating people will be when you carry yourself with dignity and choose to live DESPITE your condition.
No one can take your pain away, (although doctors can give you some lovely lovely painkillers..) but people can help you through it. But only if you accept your lot and make the most of the life you STILL HAVE.
Get better not bitter.