Stress levels.. super high!

Hello ladies I’m 20 turning 21 and literally haven’t had a normal period since I was about 17. Due to birth control and other issues. The past 2 years I been with my boyfriend and it’s super stressful. He wants to have a baby but I’m underweight and let me not conceiving as well as other issues stress me out. My question to you ladies is what are some ways you deal with stress and gain weight?? Lol