Been ttc for 4yrs

Ok so I lost a child in '13 to sids my hubbs (divorced now) were having problems i was depressed he was on drugs I tried to get him to stop tried to help him & everything in '15 we had a baby boy & i got my tubes done cause i was heart broken an didnt want to lose another baby...now here it is 4yrs later & I'm do emotional my fiance doesnt have children & he always jokes bout pregnating me lol my son has also started asking fora baby I thought I was pregnant my period was 3 days late day 2 of misperiod i took a test got a positive line the second test I took next day then period showed up im so down I'd love to be able to reverse this mistake I was in a bad place & id give anything to fix this they all want babies & I can't give it to them i feel so bad.. The tubal section is inactive i just want someone to talk to an don't know where to go