Okay, some questions:

Why did you and your first husband split?

How long have you had feelings for him? Has it been since your marriage?

Thirdly, how do you know your first husband feels the same, has he said so? How do you know he isn't just jealous because you've remarried?

You might end up losing both of them if you try to get back with him, unless you are 100% certain he would have you.

Jo.