Is it normal to get jealous of your ex-boyfriend new relationship.?

Don't know if it's normal, but is it sad? Yes.

I'd say it's 100% normal

Why should you be jealous? It's your ex for a reason, let them try and find someone who is a compatible life partner. You should find your own too.

I dunno, I wouldn't be jealous because the relationship ended. Why waste more time hurting over someone who doesn't feel the same about you?

I think if you're jealous about it, you aren't over them. Which is normal right after you break up, but you can only do that for so long before it becomes weird and/or creepy.

Definitely.

It depends on how much you still feel for them.