Advice columnist and relationship expert Matt Whyman answers:
Ending a relationship is never easy. No matter what you're going through at the time, the feelings can be intense. We're talking about the downside of love here, but the fact is you will come to terms with the situation.
Having cancer treatment can cause emotional mood swings and make you physically exhausted. If a break-up happens this can make you feel overwhelmed. If your boyfriend left because it was too hard to cope with you having cancer that adds to the hurt. If you left the relationship to focus on your needs, that could also cause complex emotions.
Talk to others
For now, turn to friends and family or a member of your care team, and let them know what you're going through. Talking to other people helps to get your feelings in perspective. It'll also help to make you aware that you don't have to deal with this alone.
Clinical psychologist Kate Hancock offered this advice: "It's very tough when you're trying to deal with too many challenges at the same time. It can feel like all your coping resources are used up. Ask to talk to your social worker or psychologist, they're used to helping young people with problems like this."
Give it time
Whatever you're feeling at this moment it's totally natural, if intense, but little by little the emotional pain will ease. Even though this break up might seem like the last thing you need right now, in time you'll feel stronger for the experience.
Bethany Scutt, a young people's community social worker adds: "It's OK to cry, rant, vent and take time to get your head around it. Take each day at a time and focus on what you need to, and can, do. Try and do one nice thing each day, even if it's small, to help you get through."
Content added: November 2015
Review due: November 2017