Should i leave my wife?

I'm a young dude half your age so my advice to you would be to have a serious talk with her about how you feel and what you want no need to mention the thought of divorce. Its not her fault that you left your eldest or your ex-wife but thats almost 20 years ago you can't change that or be angry at anyone but yourself. You sound a bit hypocritical to me that shes so wonderful and great yet your not happy, sounds like you just want a third wife i'd just reccomend talking maybe counseling therapy whatever you gotta do thats the mother of your 2 kids man. Everything you mentioned sounds trivial.... maybe take your oldest son with you to participate in your hobby or find out what he likes, 2 times a year? Really? Only you can make that change suprise her dont tell her just TAKE HER with you. Have equal time for her your kids yourself dont make everything about you. Goodluck !