Fertility problems

I’ve been wanting to be a mother since I was YOUNG. I’m 27 years old and have NEVER been pregnant I have been with my partner for 5 years and never used protection and have never been pregnant… he has a son so I know it’s not him… I was with my ex for 7 years before the person I’m with now. We got together when we was 15 and have had unprotected sex since I was 17 and I have NEVER been pregnant or seen a positive pregnancy test. I have been going to the obgyn for 2 years trying to get pregnant… they said I have pcos and I have gained weight obviously over the years but I Havnt always been so heavy, and I didn’t get pregnant before but was I reached my heaviest @ 294 I have been losing weight I’m down to 262… I have been on medication to make me have periods and I Havnt had a positive ovulation test either and thats a blood test I have done every 21 days from the start of my period but this app said my ovulation days are different than what the doctor says so I bought some at home tests and all was negative…. It’s hard to have hope….. idk what to do. All I want is to be a mother…