No Periods ever;

I m 25 and have had strange periods my whole life. I have been to numerous doctors who have done everything from putting me on the pill to regulate them (always their favorite) to ultrasounds and poking and prading. I started with my periods at 14 and had heavy periods to which made me leave class very early and several times an hour to change tampons and pads. Then I would skip periods up to 8or 9 months at a time. I had a reguar boyfriend the whole time and we were constantly worried I was pregnant. My mom took me to the doctor at about 15 which they put me on the pill until 18 yrs of age. This made my periods regular again and they came like clock work. At 18 I got married to my boyfriend and we immediatly thought we were ready for children. So I stopped taking the pill. They started again not comming at all and when they did they stopped comming heavy but now instead they started comming for a day or 2 only and real light. I never got pregnant and I tried everything even going back to the doctor to whom could not find anything wrong with me and even tried putting me on clomid to concieve which did not work after taking it for 4 months. Its immossile to count days because of there is no periiod for somtimes up to 9 or 10 months none at all!!!! not even spotting. I ended up getting pregnant in 2001 with a little boy. He was born premature and lived inthe neonatal intensive care unit for 1 month and then he died. My husband and I tried for 3 more years to have another child but the same problem consisted and we never concieved. I am now remarried for 1 yr and a half and my husband and i desperatly want a child and we are having a real tough time due to me still not having periods. I started a having a diferent symptom the last 4 months where I am bleeding all the time especially durring and after sex. I would nt call it bleeding I guess because after I wipe myself then its over no real period starts or comes at all, i hate having to wear a panty liner everyday because of the unplanned spotting. Every dr i go to can not find a problem and just suggests going on the pill which is not helping me become pregnant and is not the answer to the real problem to which this is happening to me in the first place. the pill only sugar coats the problem until I go off of it to try again for children and then the problem with no periods begin again, until recently has this spotting everyday thing began. Please tell me u have heard of such a thing and can point me to a certain type of dr. or a type of medicine or even a diagnosis of what it could be. natasha chavez 361-549-9822