Is gastric bypass reversibel? do you know any dr in sweden who can help me?

No: Gastric bypass should be seen as the last resort when all else failed. It isn't a procedure to try and have reversed later. If you are unsure about the lifelong committment required for success, you should not have the bypass surgery. Though technically possible, i don't know of any bariatric surgeon who reverses bypass electively.

Yes but rare: Yes could be reversed, if medically indicated, and if ideal weight is reached along with motivation, which rarely happens, so it is unusual to reverse, if you meets criteria, go to any major hospital, they will have a specialist available.