It's not weird at all for a guy to have stretch marks. People also get them for reasons other than weight loss; sometimes bodybuilders get them from bulking up fairly quickly.

Yes, they are permanent...I'm sorry. I waited 17 post-pregnancy years for mine to go away and still managed to be surprised that they didn't.

Think of them as your badges of courage and fortitude. You have managed to lose weight so successfully that this has happened. I know it doesn't exactly seem like a reward to you but it's the truth. Your body is changing and you can pat yourself on the back for that...the stretch marks are only incidental so ignore them...you are doing great.