am.heart broken

so me n my husband have been trying to have a baby its been 1 1/2 ye. am struggling to stay positive about it. i want to just give up. 2 years ago my husband cheated n had a baby with some one else .i have been really heart broken since.so every month that am not reminds me that i can't give him wat she did. i love my step daughter she is a blessing no matter in wat way she came into this world.i just wish i could have a baby to i have two kids with him n i love my babies. idk wat to do anymore am lost..