Depression after miscarriage

My fiancé had a problem with percosets before we started dating. He has not touched one in over 6 years. (His job drug tests once a month randomly). When we found out I had lost the first baby he went into this horrible depression mode. He never wanted to go out with our friends anymore and he would always wants to be with his mom. His mother never tried to help him with his problem she would just feed into it to keep him "happy". We found out I was pregnant again about a month ago. I lost the baby at 10 weeks. He is worse than he was the first time... Is it horrible to think he may be using again...?