I know exactly how you feel. I am a jealous type of person also.
my bf and i have made the agreement not to talk about ex's for the exact reason it makes me a lil upset. as i have gotten older i have been able to let things go more. I am only 25, but i have grown up a lot since i was 16-17. even though it gets to you and u wanna know, if oyu look at it this way why even bother? it seems like you are well aware of the fact that he likes you and is with you. You have to remember from a guys point if he didnt want to be with you he wouldnt be. my bf tells me that all the time. I dont think my bf is with anyone else, but i do sometimes quesion just his feelings for me a lone. (he doesnt show them often)
You are well aware that the past is the past, and that is where you should leave it. If you cont to ask questions it will kill your relationship. I knwo its hard trust me i know, but hes with you and thats all that matters. I dont even know how many other women before me my bf was with, i know its not a lot, but personally if i knew the number and it was a high number that would make me upset. I know him and his ex where together for 6 years. after the first three the relationship died and he stayed because he was comfortable. I have had curosity about what she looks like and things like that, but u gotta just keep telling yourself hes with you, he loves you. those girls are your past. But if its really bothering you that bad, maybe sit him down and talk abotu your feelings. dont yell or accuse just let him know this is something that is bothering you. and talk it out like adults (cant really use that expression anymore LOL ) but talk it out civil. But really in my personal opn. leave the past in the past and enjoy your time together, and dont give his ex's the satisfaction of speaking of them. Thats how my bf and i look at it. our ex's before we got together where both nuts and crazy and hurt us, so neither one of us want to give the satisfaction. and i dont think you should either! Good Luck though!

and also, you gotta be strong!!! and look at it as eventhough he dated these other girls in the end now hes with you!!

Thanks for the encouragment. It's comforting to know that there are at least some other people out there that struggle with this, too. I managed to get over/through my lunchtime stress and am looking forward to seeing him tonight for dinner and am NOT going to let myself ruin the evening by being insecure and bringing stuff up.

You just have to force yourself to ignore it. Otherwise, if you're constantly bringing up his past and making an issue out of it, he's going to get tired of being punished for having a life before he met you and give up. You obviously like this guy and think he's great. So I'm sure you don't want that to happen!

Exactly. I don't want to mess this up. It's such a vicious cycle. I stress out about him not wanting to be with me/not being good enough for him, which stresses him out, which makes him withdraw and distance himself, which makes me that much more insecure. I've just got to stop the cycle. I'm the one that started it, so I've got to just remind myself over and over that none of that stuff matters at all in terms of my relationship with him. I'm trying to take every day and just focus on that and try to live in the moment. My tendency is to ruminate on the past and/or worry about the future, but that is all counterproductive. I know these things, but it's still hard to put into action. I'm determined to stick to it because he is worth it and I'm sick of being like this.