Sexual Health - Men Forum - a Concerned / Lost / confused Husband . Please Help !

well to make a long story short. i started dating this girl in college. we would have sex for long periods of time. like 2-3 hours.. a quickie for us would be 45 minutes. we would have sex anywhere from 1 -4 times a day. i eventually got her pregnant and sex became less frequent. i was okay with that because our other responsibilities took place and it was unrealistic to do it that much doing the family thing. so about a year after our first child i couldnt last 10 minutes and then we had another child and sex was diminished to like once a month for the first six months. my children are 18 months apart so we stayed slammed.. they are now getting old enough and sleeping more where we can have sex more often. however, when we do i am not able to last more than 2 minutes tops. we have had other marital problems but we have worked those out. this is the only one lingering. she is starting to get frustrated. we use toys and oral sex to satisfy her but she is getting tired of that. she wants our sex life the way it was.. before i had perfect control and could go on queue. but now i try and i am not able to sustain the climax. it is frustrating to me where i am to the point of not enjoying it either.. i would rather her have an orgasm than i. even when i masturbate now i have a hard time sustaining it however i am able to stop it about 2 times before i am not able to control it. but as soon as i get in her and she starts moving its uncontrolable..especially if its harder than normal.. i am not use to this.

the thing that is think is different is that her walls used to be harder but now, since we have had children her walls are softer and that is a better feeling sensation to me.

has anyone else degressed like this and do you think i should go to the doctor.. io defiantly dont want it to get worse.

btw we have been seperated for a month,, not like divorcing seperated but getting everything worked out between us. i am not living at home but we are still having intercourse but this problem is the only big problem from preventing us getting back together...

it has been an issue for about a year now and i can see her frustration. but it is killing me from being away from my children and leaving at night is about the worse feeling in the world.

this whole situation has demoralized both of our self confidence. and i am very concerned about our future because of this reason.. if i figure this thing out i will come back and tell you what i did..

Ps. when she is on top it isnt as bad. when i am on top it happens immediatly.. which is strange because back in the day i could never "go" missionary style. different positions defiantly make a difference for me but missionary seems to be her favorite... its the way our bodies fit best together..

a little more info: when we first started dating i had about 5% body fat.. i gained about 65 pounds and had over 30% body fat.. i have now lost about 50 pounds since feb of this year.. do you think the weight gain and loss could have anything to do with it?